Australian and New Zealand Journal of Obstetrics and Gynaecology 2014; 54: 503–509
DOI: 10.1111/ajo.12255
Review Article
Prenatal and preconception population carrier screening for cystic fibrosis in Australia: Where are we up to? John MASSIE,1,2,3 Liane IOANNOU2 and Martin DELATYCKI2,3,4 1
Department of Respiratory Medicine, Royal Children’s Hospital, 2Murdoch Childrens Research Institute, Royal Children’s Hospital, Department of Paediatrics, University of Melbourne, Royal Children’s Hospital, Parkville, Victoria and 4Department of Clinical Genetics, Austin Health, Melbourne, Victoria, Australia
3
Aims: To describe prenatal and preconception population carrier screening for cystic fibrosis (CF) in Australia and consider progress towards establishing a universal program. Method: Medline and Embase databases (1989–2013) were searched for all publications with Australian data. Existing programs for CF carrier screening in Australia were reviewed and professional peak body websites accessed to determine recommendations. Results: Twenty-two studies met the inclusion criteria. Key stakeholder groups believe that prenatal and preconception carrier screening for CF should be available. Health-economic analyses support that CF carrier screening can be costeffective. There are small programs for CF carrier screening, in Victoria, New South Wales and Queensland. The Human Genetics Society of Australasia (HGSA) specifically recommend that screening be offered to women and couples planning a pregnancy and in the early stages of pregnancy. Other peak bodies indirectly endorse the availability of CF carrier screening. Barriers to screening include not being offered screening, the cost of testing, inequity of access and an incorrect perception that not having a family history of CF lowers risk. Conclusions: There is support for prenatal and preconception CF carrier screening by the community, health professionals and peak professional bodies in Australia. The barriers to development of a national screening program could be overcome with greater physician engagement and government support. Implications: In the interest of equity, government funded testing should be routinely offered to all pregnant women and couples planning a pregnancy. Keywords: attitudes, carrier screening, cystic fibrosis.
Introduction
Carrier screening for CF
Carrier screening for cystic fibrosis (CF) has been possible for 25 years but there has been limited progress developing prenatal and preconception population carrier screening programs in Australia.1–3 This is in the context of established prenatal screening programs for Down syndrome,4 b-thalassaemia5 and multidisease screening in Ashkenazi Jews.6 This article provides a comprehensive review of prenatal and preconception population carrier screening for CF conducted in Australia and examines the recommendations from Australian peak bodies in order to describe progress towards establishing a universal carrier screening program.
Prenatal and preconception population carrier screening for CF is offered to people without a family history of CF to identify whether they have a heterozygous mutation in the cystic fibrosis transmembrane conductance regulator (CFTR) gene. CF carriers are healthy but may have affected children if their partner is also a carrier. The decision to have carrier screening should be informed and voluntary.7,8 Prenatal and preconception population carrier screening for CF satisfies the World Health Organization (WHO) population screening guidelines and the additional guidelines on availability of education and counselling to ensure informed consent.9,10
Why offer screening for CF? Correspondence: Ass. Prof John Massie, Department of Respiratory Medicine, Royal Children’s Hospital, Flemington Road, Parkville, Vic. 3052, Australia. Email: john.massie @rch.org.au Received 18 March 2014; accepted 2 August 2014.
CF is the most common, inherited, life-shortening condition affecting Australian children. The incidence among Caucasians is 1 in 2500 and 1 in 25 are carriers.11 This means that 1 in 625 couples are carrier couples who have a 1 in 4 risk of having a baby with CF each
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pregnancy. There is no cure for CF, and the daily treatments are rigorous.12 The median age of death was 29 years in Australia in 2012,13 although babies born now are anticipated to reach 50 years on average.12
How is screening for CF done? CF is caused by mutations in the CFTR gene. To date >1900 gene alterations have been identified, with p.F508del, the most frequently occurring mutation, accounting for ~70% of all mutations.14 Screening with a panel of 12 of the most frequently occurring CFTR mutations, which are associated with severe CF phenotype, covers 84% of mutations in the Australian population.14 Therefore, individuals who obtain a negative result still have a residual risk of having an affected child (1/500).
Methodology Search strategy The electronic databases Medline (1950-present) and Embase (1980-present) were searched (latest search date: 20 December 2013). Search terms were keywords and relevant medical subject headings (MeSH) for cystic fibrosis, genetic carrier testing or screening. Search terms, combined with the term ‘cystic fibrosis’, were carrier testing, heterozygote detection, screening, genetic research, medical genetics, population genetics, pregnancy, prenatal diagnosis, preconception care, economics, behaviour, psychological processes, attitude to health, genetic counselling and genetic risk. Reference lists of identified papers were examined, and citations were tracked for potentially relevant additional studies. The search outputs were managed using Endnote (version X6). Existing programs were identified via the methods section of included studies and associated websites were searched. Program coordinators were contacted if additional information was required. Relevant organisations and professional peak bodies in Australia and each state were identified and their websites accessed to determine recommendations and guidelines with regard to prenatal and preconception population carrier screening for CF.
Criteria for inclusion The focus of this article is original research from Australia and New Zealand regarding prenatal and preconception CF carrier screening, including: current methods of offering screening, attitudes towards screening and healtheconomic evaluation.
Data analysis Meta-analysis was not possible due to the heterogeneity of the studies and the small number of studies on each area of interest.
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Results Twenty-two studies met the inclusion criteria. There were no studies from New Zealand. A narrative description of the included studies is provided.
Attitudes towards carrier screening for CF in Australia Community response to carrier screening for CF Aspects of the following studies may inform the interest on uptake of screening. The results from some of these studies have been reported previously by us in an international review.15 There are seven community-based studies from Australia that examine population attitudes to carrier screening for CF.6,16–21 In Western Australia (1995–1996), 5102 individuals of childbearing age attending GP or family planning practices completed a questionnaire about CF carrier screening, with 44% of participants electing to be tested afterwards.16 Those most likely to be screened were women planning a pregnancy, aged 25–34, born in Australia and with a tertiary (or higher) level of education. The offer of carrier screening was considered ‘passive opportunistic’, in that people were informed about CF carrier screening when attending the practices for other reasons. Testing was free, but the most influential determinant of uptake was the direct offer of screening. A focus group-based study in Victoria (2005–2006) examined community attitudes towards prenatal and preconception population carrier screening prior to the implementation of the Victorian clinical genetics services (VCGS) CF carrier screening program.17 Participants included 15 pregnant couples, 19 individuals and/or couples planning a pregnancy, 22 individuals with CF or with a family history of CF and 12 healthcare professionals. All participants believed that CF carrier screening should be made available to everyone; however, willingness to accept an offer of screening for CF was based on perceived relevance to the life stage of the participants, receiving an offer of screening from a healthcare professional and having a family history of CF. In a community study conducted in two rural NSW towns (1995), free CF carrier screening was offered through GPs, local high schools and the workplace.18 Of 610 participants, 505 had no family history of CF. The highest uptake was in the two high schools (42% and 75%) compared to the nonschool population (4%). Of the nine carriers of childbearing age who were in relationships, 6 (67%) indicated they would use prenatal diagnosis (and 5 would terminate an affected pregnancy), 2 (22%) would consider not having children and 1 (11%) was unsure. These reproductive choices were similar to those of parents with an affected child with CF diagnosed by newborn screening in Australia.22,23
© 2014 The Royal Australian and New Zealand College of Obstetricians and Gynaecologists
Population screening for cystic fibrosis in Australia
Attitudes of individuals who had CF carrier screening Two studies explored the outcomes of CF carrier screening and included carriers and noncarriers.24,25 These studies demonstrate the influences on the uptake of screening, the level of understanding, accurate recollection of results and potential harms from screening. In a follow-up study of the screened group in Victoria (2009), the attitudes of 79 carriers (whose partners tested negative) were compared with 162 noncarriers.24 Most had screening because they considered CF a severe disease (72%), and/or a doctor’s recommendation was given (58%). Fifty participants (46%) would consider termination of an affected pregnancy. There was no difference in anxiety between the carriers and noncarriers, studied 1–2 years after screening. Although couples in which one partner is identified as a carrier and the other tested negative have a higher risk of having a baby with CF (1/500, due to residual risk of the test negative partner) compared with those not tested (1/2500, the population risk), this did not concern those surveyed. Most liked the ease of cheek swab testing. The participants perceived the disadvantages of screening to be the cost and waiting for their partner’s result. Most (92%) recommended the best time to screen was before pregnancy, though few did this themselves. Most carriers (94%) recommended the test to friends and family. In a study describing the 18 month follow-up of 593 individuals who had been offered carrier screening in Western Australia (1996–1998) there were 353 replies (59%), including 43 who tested negative, 47 who tested positive and 263 who declined screening.25 Of the 47 carriers, 26 received counselling either by a GP or genetic service. Twenty-three per cent of carriers falsely believed they were only very likely to be carriers, and 33% of those who tested negative believed a negative result absolutely excluded the possibility of being a carrier. Carriers had a similar perception of their own health to noncarriers. These results reflect the importance of pre- and post-test information by educated health professionals, but that there was little evidence of harm to carriers identified by screening.
Attitudes of couples identified by CF carrier screening The attitudes of couples who were both identified as carriers of CF, through the VCGS CF carrier screening program (2006–2010), were assessed in an interviewbased study (2011–2012).26 Nine interviews were conducted, seven couples and two individuals with one couple declining to be interviewed due to coming to terms with reproductive testing outcomes. Carrier couples were not expecting a positive screening result and experienced adjustment difficulties. Six of the nine couples were pregnant at the time of screening and all had prenatal diagnosis. Two of the pregnancies were affected, with these participants reporting devastation on
receiving the result. Both couples elected termination. Three of the nine carrier couples had no further children. Of the remaining six couples, four utilised prenatal diagnosis and two PGD for subsequent pregnancies. All of the couples changed their reproductive behaviour as a result of their carrier status and informed family members of their increased risk.
Attitudes of women who declined CF screening A questionnaire study in Victoria (2009–2011) compared the attitudes of those who declined CF carrier screening27 to those who accepted it.24 There were 54 participants, who generally were well educated, aged 30–34 years and had a household income > AUD$100 000 per annum, reflecting the offer of screening predominantly through private obstetric services. The major barriers to accepting CF carrier screening were having no family history of a genetic condition (58%) or CF (54%) and would not consider a termination of pregnancy for CF (45%). Nearly, all the participants (94%) believed carrier screening for CF should be available to those who wish to have it.
Attitudes of women in the public healthcare sector not offered CF carrier screening The attitudes of those who were not offered CF carrier screening (public health sector) were compared with the attitudes of those who had been offered screening (private health sector).28 A questionnaire-based survey was administered to 185 pregnant women attending obstetric clinics at two public hospitals in Melbourne. Those who were not offered screening were significantly younger, had a lower level of education and a lower household income compared to those who were offered screening. The majority of those who were not offered screening were of Asian background, while those offered screening were mostly European. Knowledge of CF and CF screening was significantly lower in those who were not offered screening compared with those that were. Participants believed that partner’s opinion, family history of CF and perceived susceptibility of being a carrier were the most influencing factors on the decision to have screening. These are similar attitudes to those who declined screening. The majority of participants (81%) believed that carrier screening for CF should be available in the public health system, with 50% wishing they had been offered screening during their current pregnancy. Major barriers to accepting an offer in the public health system appear to be lack of knowledge of CF and CF screening, the cost of screening and diverse ethnicity.
Attitudes of obstetricians to CF carrier screening The attitudes of obstetricians to CF carrier screening were addressed by an online questionnaire sent to 1121
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Australian obstetricians in 2011.29 Of the 237 respondents, 83% supported carrier screening for CF and 97% supported carrier screening for b-thalassaemia. A small number of obstetricians reported offering carrier screening as part of routine pregnancy care (8% for CF, 20% for b-thalassaemia, 5% for fragile X syndrome, 2% for spinal muscular atrophy). The main practical barriers to screening identified were cost, time constraints and availability of supporting services. Fourteen respondents (6%) felt that population-based genetic carrier screening is best offered as part of routine pregnancy care, with most favouring preconception screening in adulthood.
severe. Of 150 respondents, 139 (93%) supported prenatal and preconception population carrier screening (4 not supportive and 7 unsure). Of 110 with partners, 56% of the partners had been tested. Of those planning a pregnancy in the future, 76% indicated they would use genetic counselling and partner testing. Most preferred the option of PGD over prenatal testing. In the theoretical situation of an affected pregnancy, 51% would terminate the pregnancy (16% would not, 33% unsure). Most felt carrier screening does not devalue the lives of people with CF, reduce the motivation to find a cure or divert resources from CF care.
Health-economic considerations Attitudes towards population carrier screening for CF by CF healthcare professionals A survey of 141 Australian CF physicians and clinic coordinators was undertaken.30 The response rate was 50%. A small majority (55%) supported prenatal and preconception population carrier screening. Many who did not support screening qualified this in terms of concern about limited resources for genetic counselling, anxiety in identified carriers and that other health programs should be given higher priority. Almost all CF clinicians rated CF as a moderate or severe disease and recognised that families find it difficult to cope with the burden of the disease. CF clinicians rated parent’s main concerns to be the daily treatments, shortened life span and impact on the family. Some of the barriers to implementing carrier screening identified were insufficient time and resources for delivery of pretest information and carrier counselling, the inability to predict clinical outcome in a disease with a variable phenotype, cost-effectiveness and the current need to pay for screening.
Attitudes to population-based CF carrier screening by people with CF It is important to consider the views of people with CF in the development of a national carrier screening program.31 There are two studies from Australia that address this issue. The first was a questionnaire sent to members of CF Western Australia in 2009.32 Of 246 members, 27 with CF replied, although 122 family members also replied. Responses from the 27 with CF were generally positive with 93% indicating that preconception screening should be offered to those of reproductive age, and 82% of the view that prenatal screening should be offered to all pregnant couples. The statements about negative aspects of screening that generated most agreement from the group with CF was that screening ‘Will reduce the motivation to find a cure/or improve treatments for CF’, ‘Will lead to discrimination of people with CF’ and ‘Will devalue the lives of people with CF’. The other study was based on a questionnaire sent to 291 adults with CF in Victoria (2011).33 The response rate was 52%. Eighty-one per cent rated CF as a severe disease, although only 41% rated their own disease as 506
There are four health-economic studies on CF carrier screening using Australian data.34–37 The Department of Population Health, WA, developed a decision tree to estimate costs and outcomes for different screening models.34 Cost of care was derived from estimates of the annual cost of CF inpatient and outpatient services and estimated annual health sector costs between AUD $23 424 (children) and AUD$19 425 (adults).34 This equated to a lifetime cost of AUD$508 370 (2008) with discounting.34 This accounted for direct health systems costs, but excluded indirect costs and was at the lower end of CF cost of care compared with overseas studies.38 Three models of carrier screening were explored, one-step, two-step simultaneous and two-step sequential. The annual cost for prenatal CF carrier screening was estimated at AUD$5.32 million (one-step), AUD $3.35 million (two-step simultaneous) and AUD $2.93 million (two-step sequential). Annual costs would be expected to be lower once a program was established and their model took into account savings for subsequent pregnancies. They concluded that under some scenarios, prenatal CF carrier screening is cost-saving, but was not conclusive. They highlighted the need for investment of funds in the short term.34 The Centre for Health Economic Evaluation and Research (CHERE, University of Technology, Sydney) used the Australian CF database to generate a model of CF costing, taking into account patient severity.35 This used only direct medical costs, and calculated the mean annual cost of care as AUD$17 236 and lifetime cost of care as AUD$338 059 (2013).35 In Australia, there are approximately 3000 people with CF and this equates to an annual cost of AUD$67 million. The CHERE group then investigated the costeffectiveness of a combined prenatal and preconception CF screening program in Australia, using a decision tree to integrate the effect of information from initial pregnancies on subsequent reproductive decisions. The screening program was estimated to reduce the annual incidence of CF births by 53% overall, and 64% in subsequent pregnancies. In initial pregnancies, the costs in the screening arm (AUD$16.6 million/100 000 births) exceed those in the nonscreening arm (AUD$13.4 million/
© 2014 The Royal Australian and New Zealand College of Obstetricians and Gynaecologists
Population screening for cystic fibrosis in Australia
100 000 births).36 However, the costs accrued in the nonscreening arm exceed those in the screening arm for subsequent pregnancies. When initial and subsequent pregnancies are considered together, the results indicate that screening is cost-saving. The cost-effectiveness of the school-based Tay-Sachs and CF carrier screening in Australia (2005) indicated that preconception carrier screening cost AUD$530 000 per birth averted. The study concluded that their high school screening model offered comparable costeffectiveness to prenatal screening programs, but derived data on cost of care from available international studies.37
Peak professional bodies In Australia, the Human Genetics Society of Australasia (HGSA, 2013) recommends that ‘all couples intending to have children, or who are pregnant, should be made aware of the availability of CF carrier screening.’39 While the Royal Australian and New Zealand College of Obstetricians and Gynaecologists (RANZCOG, 2013) do not specify CF they recommend that ‘at prepregnancy or early in the antenatal period counselling should address availability of carrier status screening for genetic conditions of perceived high prevalence or consequence’ which is relevant to CF.5 This is similar to the Royal Australian College of General Practitioners (RACGP) who recommend that the opportunity for CF carrier screening be provided to those of Northern European ethnic background.40 The support organisations, CF Western Australia (CFWA) and CF Victoria (CFV) have position statements regarding prenatal and preconception population carrier screening for CF. CFWA’s policy recommends widespread availability but emphasises the need for genetic counselling for carriers.41 CFV released a statement supporting prenatal and preconception population carrier screening for CF ‘as an opportunity for people to make informed life and reproductive choices in relation to CF’.42
Prenatal and preconception population carrier screening programs for CF in Australia Relatively small programs exist in Victoria, New South Wales and Queensland (Table 1). Prenatal and preconception population carrier screening for CF may be
available through smaller IVF clinics in the other states/ territories.
Victoria Victorian clinical genetics services. A CF carrier screening program in Victoria commenced in 2006. The first 3 years of the program were reported in ANZJOG,43 and to date over 10 000 people have been screened.43 Pretest information was provided by private obstetricians or GPs with information brochures and a website (www. cfscreening.com.au). Two-step testing was conducted via the use of a buccal swab for 38 CFTR mutations at a cost $220. In 2012, the program was extended to include screening for spinal muscular atrophy and fragile X syndrome. Healthscope. A private pathology laboratory in Victoria offers CF carrier screening to individuals over the age of 18 years at a cost of AUD$150, including access to free genetic counselling if found to be a carrier. Two-step testing is conducted via cheek swab and the sample is screened for 44 different CFTR mutations (www.thecftest.com.au).
New South Wales Hunter genetics. This clinic in Newcastle, NSW offers CF population screening. Expanded one-step screening is conducted by mouthwash on a fee-for-service basis, $50 per individual, for p.F508del only. If one partner is found to be a carrier the other partners sample is screened for an additional 50 CFTR gene mutations at no additional cost. A study of 730 people screened with no family history of CF and 270 with a family history found 27 carriers (4%) from those with no family history, and two of these had carrier partners.44 All carrier couples changed their reproductive decisions to avoid having a child with CF. Genea. Genea (formerly Sydney IVF) offers CF carrier screening to those who are seeking infertility treatment with the choice of One- or Two-step method of testing. A blood test is used to screen for more than 90 CFTR mutations.
Queensland The Queensland fertility group. The Queensland Fertility Group offers screening to infertile patients, using a panel of 30 CFTR mutations. Two-step screening is provided using a blood test. They recently screened 5600
Table 1 Overview of prenatal and preconception population CF carrier screening programs in Australia State
Program
Population
Method
Model
VIC
VCGS RGCS VCGS CF carrier screening program Healthscope Hunter genetics Genea (formerly Sydney IVF)
Private Health Sector Private Health Sector Direct-to-Consumer Direct-to-Consumer IVF
Blood Test Buccal Swab Buccal Swab Mouthwash Blood Test
The Queensland fertility group
IVF
Blood Test
Two-Step Two-Step Two-Step One-Step One-Step Two-Step Two-Step
NSW
QLD
Panel 38 38 44 1† >90 30
Cost $385.00 $150.00 $150.00 $50.00 $550.00 $350.00 $270.00
†If positive, partner is screened for a further 50 gene alterations (at no cost to consumer).
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patients (mostly women) and found a carrier rate of 1 in 21.5.45
The future of population-based carrier screening in Australia There was significant support for prenatal and preconception CF carrier screening by the general community, CF community and health professionals. Only the HGSA has a definitive recommendation about CF. Individuals and couples value screening and carrier couples use the information to make reproductive choices to avoid having a child with CF. Furthermore, individuals and couples value a direct offer of screening from doctors, as uptake is higher when offered in routine settings. However, there are major barriers with regard to offering and accepting population carrier screening for CF, including cost of testing, inequity of access, inaccurate perception that not having a family history of CF lowers risk, time constraints as well as lack of knowledge and available resources for health professionals and no universal standard model of screening in Australia. The CF carrier screening programs in Victoria and New South Wales are small but slowly expanding. Whether the HGSA statement will encourage carrier screening in other states remains to be seen. Greater engagement with obstetricians and GPs is required to expand carrier screening in its current form. There are a number of possibilities for a national CF carrier screening program in Australia. This might be an expansion of the current fee-for-service model, but this does not address equity of access. Government funding for screening would address this issue but it is critical that funding is not only for the cost of the test but also for all services required to provide a screening program, including genetic counselling and prenatal and pre-implantation testing. A more sophisticated model would include a formal program with central governing committee to oversee standards of test delivery and follow-up.
Acknowledgements Author MBD is a consultant to Healthscope Pathology. This study was supported by the Victorian Government’s Operational Infrastructure Support Program.
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4 Prenatal screening tests for trisomy 21 (Down syndrome), trisomy 18 (Edwards syndrome) and neural tube defects. A Guideline developed by the Human Genetics Society of Australasia (HGSA) and the Royal Australian and New Zealand College of Obstetricians and Gynaecologists (RANZCOG), 2010. [Accessed 15 October 2010]. Available from URL: http://www.ranzcog.edu.au/publications/college statements.shtml 5 Prenatal Screening for Fetal Abnormalities. A Statement from the The Royal Australian and New Zealand College of Obstetricians and Gynaecologists, 2013. [Accessed 15 October 2013]. Available from URL: http://www.ranzcog.edu.au/ college-statements-guidelines.html 6 Barlow-Stewart K, Burnett L, Proos A et al. A genetic screening programme for Tay-Sachs disease and cystic fibrosis for Australian Jewish high school students. J Med Genet 2003; 40 (4): e45. 7 Grosse SD, Rogowski WH, Ross LF et al. Population screening for genetic disorders in the 21st century: evidence, economics, and ethics. Public Health Genomics 2010; 13: 106– 115. 8 Castellani C, Macek M Jr, Cassiman JJ et al. Benchmarks for cystic fibrosis carrier screening: a European consensus document. J Cyst Fibros 2010; 9: 165–178. 9 Wilson JM, Junger J. Prinicipals and Practice of Screening for Disease. Geneva: World Health Organization, 1968. Public Health Paper, Number 34. 10 Khoury MJ, McCabe LL, McCabe ER. Population screening in the age of genomic medicine. N Engl J Med 2003; 348 (1): 50–58. 11 Massie RJ, Olsen M, Glazner J et al. Newborn screening for cystic fibrosis in Victoria: 10 years’ experience (1989–1998). Med J Aust 2000; 172: 584–587. 12 Dodge JA, Lewis PA, Stanton M, Wilsher J. Cystic fibrosis mortality and survival in the UK: 1947–2003. Eur Respir J 2007; 29: 522–526. 13 Australian Cystic Fibrosis Data Registry Annual Report. Published by Cystic Fibrosis Australia 2012. [Accessed 11 September 2013]. Available from URL: http://www.cysticfibrosis. org.au/ media/wysiwyg/CF-Australia/05_CFA_Annual_Review_ 2013.pdf 14 Bobadilla JL, Macek M Jr, Fine JP, Farrell PM. Cystic fibrosis: a worldwide analysis of CFTR mutations–correlation with incidence data and application to screening. Hum Mutat 2002; 19: 575–606. 15 Massie J, Delatycki MB. Cystic fibrosis carrier screening. Paediatr Respir Rev 2013; 14: 270–275. 16 Honnor M, Zubrick SR, Walpole I et al. Population screening for cystic fibrosis in Western Australia: community response. Am J Med Genet 2000; 93: 198–204. 17 McClaren BJ, Delatycki MB, Collins V et al. ‘It is not in my world’: an exploration of attitudes and influences associated with cystic fibrosis carrier screening. Eur J Hum Genet 2008; 16: 435–444. 18 Wake SA, Rogers CJ, Colley PW et al. Cystic fibrosis carrier screening in two New South Wales country towns. Med J Aust 1996; 164: 471–474. 19 Ioannou L, Massie J, Lewis S et al. Evaluation of a multidisease carrier screening programme in Ashkenazi Jewish high schools. Clin Genet 2010; 78 (1): 21–31.
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20 Gason AA, Sheffield E, Bankier A et al. Evaluation of a TaySachs disease screening program. Clin Genet 2003; 63: 386– 392. 21 Hall J, Fiebig DG, King MT et al. What influences participation in genetic carrier testing? Results from a discrete choice experiment. J Health Econ 2006; 25: 520–537. 22 Sawyer SM, Cerritelli B, Carter LS et al. Changing their minds with time: a comparison of hypothetical and actual reproductive behaviors in parents of children with cystic fibrosis. Pediatrics 2006; 118: e649–e656. 23 Dudding T, Wilcken B, Burgess B et al. Reproductive decisions after neonatal screening identifies cystic fibrosis. Arch Dis Child Fetal Neonatal Ed 2000; 82: F124–F127. 24 Ioannou L, Massie J, Collins V et al. Population-based genetic screening for cystic fibrosis: attitudes and outcomes. Public Health Genomics 2010; 13: 449–456. 25 Gordon C, Walpole I, Zubrick SR, Bower C. Population screening for cystic fibrosis: knowledge and emotional consequences 18 months later. Am J Med Genet 2003; 120A: 199–208. 26 Ioannou L, Delatycki MB, Massie J et al. Experiences of couples both identified as carriers of cystic fibrosis identified through a population-based carrier screening program. Poster presentation Human Genetics Society of Australasia. New Zealand 2013. Twin Res Hum Genet 2013; 16: 904. 27 Ioannou L, Massie J, Lewis S et al. ‘No Thanks’-reasons why pregnant women declined an offer of cystic fibrosis carrier screening. J Com Genet 2013; 5(2): 109–117. 28 Ioannou L, Massie J, Lewis S et al. Attitudes and opinions of pregnant women who are not offered cystic fibrosis carrier screening. Eur J Hum Genet 2013; 22: 859–865. 29 Stark Z, Massie J, McClaren B et al. Current practice and attitudes of Australian obstetricians toward population-based carrier screening for inherited conditions. Twin Res Hum Genet 2013; 16: 601–607. 30 Cunningham F, Lewis S, Curnow L et al. Respiratory physicians and clinic coordinators’ attitudes to populationbased cystic fibrosis carrier screening. J Cyst Fibros 2014; 13: 99–105. 31 Genetic testing for cystic fibrosis. National Institutes of Health Consensus Development Conference Statement on genetic testing for cystic fibrosis. Arch Intern Med 1999; 159: 1529– 1539. 32 Maxwell SJ, Kyne G, Molster C et al. Perceptions of population cystic fibrosis prenatal and preconception carrier screening among individuals with cystic fibrosis and their family members. Genet Test Mol Biomarkers 2011; 15: 159– 164.
33 Leaver A, Macciocca I, Lewis S et al. Attitudes of adults with cystic fibrosis towards population-based cystic fibrosis carrier screening. Oral presentation Human Genetics Society of Australasia. Canberra 2012. Twin Res Hum Genet 2012; 15 (4): 570. 34 Maxwell S, Brameld K, Youngs L et al. Informing policy for the Australian context – Costs, outcomes and cost savings of prenatal carrier screening for cystic fibrosis. Aust N Z J Obstet Gynaecol 2010; 50 (1): 51–59. 35 Van Gool K, Norman RP, Delatycki MB et al. Understanding the costs of care for cystic fibrosis: an analysis by age and health state. Value Health 2013; 16: 345–355. 36 Norman RP, Van Gool K, Hall J et al. Cost-effectiveness of carrier screening for cystic fibrosis in Australia. J Cyst Fibros 2012; 11: 281–287. 37 Warren E, Anderson R, Proos AL et al. Cost-effectiveness of a school-based Tay-Sachs and cystic fibrosis genetic carrier screening program. Genet Med 2005; 7: 484–494. 38 Massie J, Castellani C, Grody WW. Carrier screening for cystic fibrosis in the new era of medications that restore CFTR function. Lancet 2014; 383: 923–925. 39 Population-based carrier screening for cystic fibrosis. Position Statement by the Human Genetics Society of Australasia, 2013. [Accessed 11 March 2014]. Available from URL: http://www. hgsa.org.au/documents/item/1282 40 Royal Australian Community of General Practitioners. Guidelines for preventive activities in general practice, 8th edn. Published by RACGP House, 2013. [Accessed 12 May 2014]. Available from URL: http://www.racgp.org.au/your-practice/ guidelines/redbook/ genetic-counselling-and-testing/ 41 Public policy on community-wide preconception and prenatal carrier screening for cystic fibrosis genotypes. Cystic Fibrosis Association of Western Australia Inc., 2010. [Accessed 16 September 2013]. Available from URL: http://www. cysticfibrosis.org.au 42 Knowing your Genes – Cystic Fibrosis Carrier Screening. Cystic Fibrosis Victoria, 2014. [Accessed 2 June 2014]. Available from URL: http://www.cysticfibrosis.org.au/vic/ carrier-screening 43 Massie J, Petrou V, Forbes R et al. Population-based carrier screening for cystic fibrosis in Victoria: the first three years’ experience. Aust N Z J Obstet Gynaecol 2009; 49: 484–489. 44 Christie LM, Ingrey AJ, Turner GM et al. Outcomes of a cystic fibrosis carrier testing clinic for couples. Med J Aust 2009; 191: 499–501. 45 Field PD, Martin NJ. CFTR mutation screening in an assisted reproductive clinic. Aust N Z J Obstet Gynaecol 2011; 51: 536–539.
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DOI: 10.1111/ajo.12255
Review Article
Prenatal and preconception population carrier screening for cystic fibrosis in Australia: Where are we up to? John MASSIE,1,2,3 Liane IOANNOU2 and Martin DELATYCKI2,3,4 1
Department of Respiratory Medicine, Royal Children’s Hospital, 2Murdoch Childrens Research Institute, Royal Children’s Hospital, Department of Paediatrics, University of Melbourne, Royal Children’s Hospital, Parkville, Victoria and 4Department of Clinical Genetics, Austin Health, Melbourne, Victoria, Australia
3
Aims: To describe prenatal and preconception population carrier screening for cystic fibrosis (CF) in Australia and consider progress towards establishing a universal program. Method: Medline and Embase databases (1989–2013) were searched for all publications with Australian data. Existing programs for CF carrier screening in Australia were reviewed and professional peak body websites accessed to determine recommendations. Results: Twenty-two studies met the inclusion criteria. Key stakeholder groups believe that prenatal and preconception carrier screening for CF should be available. Health-economic analyses support that CF carrier screening can be costeffective. There are small programs for CF carrier screening, in Victoria, New South Wales and Queensland. The Human Genetics Society of Australasia (HGSA) specifically recommend that screening be offered to women and couples planning a pregnancy and in the early stages of pregnancy. Other peak bodies indirectly endorse the availability of CF carrier screening. Barriers to screening include not being offered screening, the cost of testing, inequity of access and an incorrect perception that not having a family history of CF lowers risk. Conclusions: There is support for prenatal and preconception CF carrier screening by the community, health professionals and peak professional bodies in Australia. The barriers to development of a national screening program could be overcome with greater physician engagement and government support. Implications: In the interest of equity, government funded testing should be routinely offered to all pregnant women and couples planning a pregnancy. Keywords: attitudes, carrier screening, cystic fibrosis.
Introduction
Carrier screening for CF
Carrier screening for cystic fibrosis (CF) has been possible for 25 years but there has been limited progress developing prenatal and preconception population carrier screening programs in Australia.1–3 This is in the context of established prenatal screening programs for Down syndrome,4 b-thalassaemia5 and multidisease screening in Ashkenazi Jews.6 This article provides a comprehensive review of prenatal and preconception population carrier screening for CF conducted in Australia and examines the recommendations from Australian peak bodies in order to describe progress towards establishing a universal carrier screening program.
Prenatal and preconception population carrier screening for CF is offered to people without a family history of CF to identify whether they have a heterozygous mutation in the cystic fibrosis transmembrane conductance regulator (CFTR) gene. CF carriers are healthy but may have affected children if their partner is also a carrier. The decision to have carrier screening should be informed and voluntary.7,8 Prenatal and preconception population carrier screening for CF satisfies the World Health Organization (WHO) population screening guidelines and the additional guidelines on availability of education and counselling to ensure informed consent.9,10
Why offer screening for CF? Correspondence: Ass. Prof John Massie, Department of Respiratory Medicine, Royal Children’s Hospital, Flemington Road, Parkville, Vic. 3052, Australia. Email: john.massie @rch.org.au Received 18 March 2014; accepted 2 August 2014.
CF is the most common, inherited, life-shortening condition affecting Australian children. The incidence among Caucasians is 1 in 2500 and 1 in 25 are carriers.11 This means that 1 in 625 couples are carrier couples who have a 1 in 4 risk of having a baby with CF each
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pregnancy. There is no cure for CF, and the daily treatments are rigorous.12 The median age of death was 29 years in Australia in 2012,13 although babies born now are anticipated to reach 50 years on average.12
How is screening for CF done? CF is caused by mutations in the CFTR gene. To date >1900 gene alterations have been identified, with p.F508del, the most frequently occurring mutation, accounting for ~70% of all mutations.14 Screening with a panel of 12 of the most frequently occurring CFTR mutations, which are associated with severe CF phenotype, covers 84% of mutations in the Australian population.14 Therefore, individuals who obtain a negative result still have a residual risk of having an affected child (1/500).
Methodology Search strategy The electronic databases Medline (1950-present) and Embase (1980-present) were searched (latest search date: 20 December 2013). Search terms were keywords and relevant medical subject headings (MeSH) for cystic fibrosis, genetic carrier testing or screening. Search terms, combined with the term ‘cystic fibrosis’, were carrier testing, heterozygote detection, screening, genetic research, medical genetics, population genetics, pregnancy, prenatal diagnosis, preconception care, economics, behaviour, psychological processes, attitude to health, genetic counselling and genetic risk. Reference lists of identified papers were examined, and citations were tracked for potentially relevant additional studies. The search outputs were managed using Endnote (version X6). Existing programs were identified via the methods section of included studies and associated websites were searched. Program coordinators were contacted if additional information was required. Relevant organisations and professional peak bodies in Australia and each state were identified and their websites accessed to determine recommendations and guidelines with regard to prenatal and preconception population carrier screening for CF.
Criteria for inclusion The focus of this article is original research from Australia and New Zealand regarding prenatal and preconception CF carrier screening, including: current methods of offering screening, attitudes towards screening and healtheconomic evaluation.
Data analysis Meta-analysis was not possible due to the heterogeneity of the studies and the small number of studies on each area of interest.
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Results Twenty-two studies met the inclusion criteria. There were no studies from New Zealand. A narrative description of the included studies is provided.
Attitudes towards carrier screening for CF in Australia Community response to carrier screening for CF Aspects of the following studies may inform the interest on uptake of screening. The results from some of these studies have been reported previously by us in an international review.15 There are seven community-based studies from Australia that examine population attitudes to carrier screening for CF.6,16–21 In Western Australia (1995–1996), 5102 individuals of childbearing age attending GP or family planning practices completed a questionnaire about CF carrier screening, with 44% of participants electing to be tested afterwards.16 Those most likely to be screened were women planning a pregnancy, aged 25–34, born in Australia and with a tertiary (or higher) level of education. The offer of carrier screening was considered ‘passive opportunistic’, in that people were informed about CF carrier screening when attending the practices for other reasons. Testing was free, but the most influential determinant of uptake was the direct offer of screening. A focus group-based study in Victoria (2005–2006) examined community attitudes towards prenatal and preconception population carrier screening prior to the implementation of the Victorian clinical genetics services (VCGS) CF carrier screening program.17 Participants included 15 pregnant couples, 19 individuals and/or couples planning a pregnancy, 22 individuals with CF or with a family history of CF and 12 healthcare professionals. All participants believed that CF carrier screening should be made available to everyone; however, willingness to accept an offer of screening for CF was based on perceived relevance to the life stage of the participants, receiving an offer of screening from a healthcare professional and having a family history of CF. In a community study conducted in two rural NSW towns (1995), free CF carrier screening was offered through GPs, local high schools and the workplace.18 Of 610 participants, 505 had no family history of CF. The highest uptake was in the two high schools (42% and 75%) compared to the nonschool population (4%). Of the nine carriers of childbearing age who were in relationships, 6 (67%) indicated they would use prenatal diagnosis (and 5 would terminate an affected pregnancy), 2 (22%) would consider not having children and 1 (11%) was unsure. These reproductive choices were similar to those of parents with an affected child with CF diagnosed by newborn screening in Australia.22,23
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Attitudes of individuals who had CF carrier screening Two studies explored the outcomes of CF carrier screening and included carriers and noncarriers.24,25 These studies demonstrate the influences on the uptake of screening, the level of understanding, accurate recollection of results and potential harms from screening. In a follow-up study of the screened group in Victoria (2009), the attitudes of 79 carriers (whose partners tested negative) were compared with 162 noncarriers.24 Most had screening because they considered CF a severe disease (72%), and/or a doctor’s recommendation was given (58%). Fifty participants (46%) would consider termination of an affected pregnancy. There was no difference in anxiety between the carriers and noncarriers, studied 1–2 years after screening. Although couples in which one partner is identified as a carrier and the other tested negative have a higher risk of having a baby with CF (1/500, due to residual risk of the test negative partner) compared with those not tested (1/2500, the population risk), this did not concern those surveyed. Most liked the ease of cheek swab testing. The participants perceived the disadvantages of screening to be the cost and waiting for their partner’s result. Most (92%) recommended the best time to screen was before pregnancy, though few did this themselves. Most carriers (94%) recommended the test to friends and family. In a study describing the 18 month follow-up of 593 individuals who had been offered carrier screening in Western Australia (1996–1998) there were 353 replies (59%), including 43 who tested negative, 47 who tested positive and 263 who declined screening.25 Of the 47 carriers, 26 received counselling either by a GP or genetic service. Twenty-three per cent of carriers falsely believed they were only very likely to be carriers, and 33% of those who tested negative believed a negative result absolutely excluded the possibility of being a carrier. Carriers had a similar perception of their own health to noncarriers. These results reflect the importance of pre- and post-test information by educated health professionals, but that there was little evidence of harm to carriers identified by screening.
Attitudes of couples identified by CF carrier screening The attitudes of couples who were both identified as carriers of CF, through the VCGS CF carrier screening program (2006–2010), were assessed in an interviewbased study (2011–2012).26 Nine interviews were conducted, seven couples and two individuals with one couple declining to be interviewed due to coming to terms with reproductive testing outcomes. Carrier couples were not expecting a positive screening result and experienced adjustment difficulties. Six of the nine couples were pregnant at the time of screening and all had prenatal diagnosis. Two of the pregnancies were affected, with these participants reporting devastation on
receiving the result. Both couples elected termination. Three of the nine carrier couples had no further children. Of the remaining six couples, four utilised prenatal diagnosis and two PGD for subsequent pregnancies. All of the couples changed their reproductive behaviour as a result of their carrier status and informed family members of their increased risk.
Attitudes of women who declined CF screening A questionnaire study in Victoria (2009–2011) compared the attitudes of those who declined CF carrier screening27 to those who accepted it.24 There were 54 participants, who generally were well educated, aged 30–34 years and had a household income > AUD$100 000 per annum, reflecting the offer of screening predominantly through private obstetric services. The major barriers to accepting CF carrier screening were having no family history of a genetic condition (58%) or CF (54%) and would not consider a termination of pregnancy for CF (45%). Nearly, all the participants (94%) believed carrier screening for CF should be available to those who wish to have it.
Attitudes of women in the public healthcare sector not offered CF carrier screening The attitudes of those who were not offered CF carrier screening (public health sector) were compared with the attitudes of those who had been offered screening (private health sector).28 A questionnaire-based survey was administered to 185 pregnant women attending obstetric clinics at two public hospitals in Melbourne. Those who were not offered screening were significantly younger, had a lower level of education and a lower household income compared to those who were offered screening. The majority of those who were not offered screening were of Asian background, while those offered screening were mostly European. Knowledge of CF and CF screening was significantly lower in those who were not offered screening compared with those that were. Participants believed that partner’s opinion, family history of CF and perceived susceptibility of being a carrier were the most influencing factors on the decision to have screening. These are similar attitudes to those who declined screening. The majority of participants (81%) believed that carrier screening for CF should be available in the public health system, with 50% wishing they had been offered screening during their current pregnancy. Major barriers to accepting an offer in the public health system appear to be lack of knowledge of CF and CF screening, the cost of screening and diverse ethnicity.
Attitudes of obstetricians to CF carrier screening The attitudes of obstetricians to CF carrier screening were addressed by an online questionnaire sent to 1121
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Australian obstetricians in 2011.29 Of the 237 respondents, 83% supported carrier screening for CF and 97% supported carrier screening for b-thalassaemia. A small number of obstetricians reported offering carrier screening as part of routine pregnancy care (8% for CF, 20% for b-thalassaemia, 5% for fragile X syndrome, 2% for spinal muscular atrophy). The main practical barriers to screening identified were cost, time constraints and availability of supporting services. Fourteen respondents (6%) felt that population-based genetic carrier screening is best offered as part of routine pregnancy care, with most favouring preconception screening in adulthood.
severe. Of 150 respondents, 139 (93%) supported prenatal and preconception population carrier screening (4 not supportive and 7 unsure). Of 110 with partners, 56% of the partners had been tested. Of those planning a pregnancy in the future, 76% indicated they would use genetic counselling and partner testing. Most preferred the option of PGD over prenatal testing. In the theoretical situation of an affected pregnancy, 51% would terminate the pregnancy (16% would not, 33% unsure). Most felt carrier screening does not devalue the lives of people with CF, reduce the motivation to find a cure or divert resources from CF care.
Health-economic considerations Attitudes towards population carrier screening for CF by CF healthcare professionals A survey of 141 Australian CF physicians and clinic coordinators was undertaken.30 The response rate was 50%. A small majority (55%) supported prenatal and preconception population carrier screening. Many who did not support screening qualified this in terms of concern about limited resources for genetic counselling, anxiety in identified carriers and that other health programs should be given higher priority. Almost all CF clinicians rated CF as a moderate or severe disease and recognised that families find it difficult to cope with the burden of the disease. CF clinicians rated parent’s main concerns to be the daily treatments, shortened life span and impact on the family. Some of the barriers to implementing carrier screening identified were insufficient time and resources for delivery of pretest information and carrier counselling, the inability to predict clinical outcome in a disease with a variable phenotype, cost-effectiveness and the current need to pay for screening.
Attitudes to population-based CF carrier screening by people with CF It is important to consider the views of people with CF in the development of a national carrier screening program.31 There are two studies from Australia that address this issue. The first was a questionnaire sent to members of CF Western Australia in 2009.32 Of 246 members, 27 with CF replied, although 122 family members also replied. Responses from the 27 with CF were generally positive with 93% indicating that preconception screening should be offered to those of reproductive age, and 82% of the view that prenatal screening should be offered to all pregnant couples. The statements about negative aspects of screening that generated most agreement from the group with CF was that screening ‘Will reduce the motivation to find a cure/or improve treatments for CF’, ‘Will lead to discrimination of people with CF’ and ‘Will devalue the lives of people with CF’. The other study was based on a questionnaire sent to 291 adults with CF in Victoria (2011).33 The response rate was 52%. Eighty-one per cent rated CF as a severe disease, although only 41% rated their own disease as 506
There are four health-economic studies on CF carrier screening using Australian data.34–37 The Department of Population Health, WA, developed a decision tree to estimate costs and outcomes for different screening models.34 Cost of care was derived from estimates of the annual cost of CF inpatient and outpatient services and estimated annual health sector costs between AUD $23 424 (children) and AUD$19 425 (adults).34 This equated to a lifetime cost of AUD$508 370 (2008) with discounting.34 This accounted for direct health systems costs, but excluded indirect costs and was at the lower end of CF cost of care compared with overseas studies.38 Three models of carrier screening were explored, one-step, two-step simultaneous and two-step sequential. The annual cost for prenatal CF carrier screening was estimated at AUD$5.32 million (one-step), AUD $3.35 million (two-step simultaneous) and AUD $2.93 million (two-step sequential). Annual costs would be expected to be lower once a program was established and their model took into account savings for subsequent pregnancies. They concluded that under some scenarios, prenatal CF carrier screening is cost-saving, but was not conclusive. They highlighted the need for investment of funds in the short term.34 The Centre for Health Economic Evaluation and Research (CHERE, University of Technology, Sydney) used the Australian CF database to generate a model of CF costing, taking into account patient severity.35 This used only direct medical costs, and calculated the mean annual cost of care as AUD$17 236 and lifetime cost of care as AUD$338 059 (2013).35 In Australia, there are approximately 3000 people with CF and this equates to an annual cost of AUD$67 million. The CHERE group then investigated the costeffectiveness of a combined prenatal and preconception CF screening program in Australia, using a decision tree to integrate the effect of information from initial pregnancies on subsequent reproductive decisions. The screening program was estimated to reduce the annual incidence of CF births by 53% overall, and 64% in subsequent pregnancies. In initial pregnancies, the costs in the screening arm (AUD$16.6 million/100 000 births) exceed those in the nonscreening arm (AUD$13.4 million/
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100 000 births).36 However, the costs accrued in the nonscreening arm exceed those in the screening arm for subsequent pregnancies. When initial and subsequent pregnancies are considered together, the results indicate that screening is cost-saving. The cost-effectiveness of the school-based Tay-Sachs and CF carrier screening in Australia (2005) indicated that preconception carrier screening cost AUD$530 000 per birth averted. The study concluded that their high school screening model offered comparable costeffectiveness to prenatal screening programs, but derived data on cost of care from available international studies.37
Peak professional bodies In Australia, the Human Genetics Society of Australasia (HGSA, 2013) recommends that ‘all couples intending to have children, or who are pregnant, should be made aware of the availability of CF carrier screening.’39 While the Royal Australian and New Zealand College of Obstetricians and Gynaecologists (RANZCOG, 2013) do not specify CF they recommend that ‘at prepregnancy or early in the antenatal period counselling should address availability of carrier status screening for genetic conditions of perceived high prevalence or consequence’ which is relevant to CF.5 This is similar to the Royal Australian College of General Practitioners (RACGP) who recommend that the opportunity for CF carrier screening be provided to those of Northern European ethnic background.40 The support organisations, CF Western Australia (CFWA) and CF Victoria (CFV) have position statements regarding prenatal and preconception population carrier screening for CF. CFWA’s policy recommends widespread availability but emphasises the need for genetic counselling for carriers.41 CFV released a statement supporting prenatal and preconception population carrier screening for CF ‘as an opportunity for people to make informed life and reproductive choices in relation to CF’.42
Prenatal and preconception population carrier screening programs for CF in Australia Relatively small programs exist in Victoria, New South Wales and Queensland (Table 1). Prenatal and preconception population carrier screening for CF may be
available through smaller IVF clinics in the other states/ territories.
Victoria Victorian clinical genetics services. A CF carrier screening program in Victoria commenced in 2006. The first 3 years of the program were reported in ANZJOG,43 and to date over 10 000 people have been screened.43 Pretest information was provided by private obstetricians or GPs with information brochures and a website (www. cfscreening.com.au). Two-step testing was conducted via the use of a buccal swab for 38 CFTR mutations at a cost $220. In 2012, the program was extended to include screening for spinal muscular atrophy and fragile X syndrome. Healthscope. A private pathology laboratory in Victoria offers CF carrier screening to individuals over the age of 18 years at a cost of AUD$150, including access to free genetic counselling if found to be a carrier. Two-step testing is conducted via cheek swab and the sample is screened for 44 different CFTR mutations (www.thecftest.com.au).
New South Wales Hunter genetics. This clinic in Newcastle, NSW offers CF population screening. Expanded one-step screening is conducted by mouthwash on a fee-for-service basis, $50 per individual, for p.F508del only. If one partner is found to be a carrier the other partners sample is screened for an additional 50 CFTR gene mutations at no additional cost. A study of 730 people screened with no family history of CF and 270 with a family history found 27 carriers (4%) from those with no family history, and two of these had carrier partners.44 All carrier couples changed their reproductive decisions to avoid having a child with CF. Genea. Genea (formerly Sydney IVF) offers CF carrier screening to those who are seeking infertility treatment with the choice of One- or Two-step method of testing. A blood test is used to screen for more than 90 CFTR mutations.
Queensland The Queensland fertility group. The Queensland Fertility Group offers screening to infertile patients, using a panel of 30 CFTR mutations. Two-step screening is provided using a blood test. They recently screened 5600
Table 1 Overview of prenatal and preconception population CF carrier screening programs in Australia State
Program
Population
Method
Model
VIC
VCGS RGCS VCGS CF carrier screening program Healthscope Hunter genetics Genea (formerly Sydney IVF)
Private Health Sector Private Health Sector Direct-to-Consumer Direct-to-Consumer IVF
Blood Test Buccal Swab Buccal Swab Mouthwash Blood Test
The Queensland fertility group
IVF
Blood Test
Two-Step Two-Step Two-Step One-Step One-Step Two-Step Two-Step
NSW
QLD
Panel 38 38 44 1† >90 30
Cost $385.00 $150.00 $150.00 $50.00 $550.00 $350.00 $270.00
†If positive, partner is screened for a further 50 gene alterations (at no cost to consumer).
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patients (mostly women) and found a carrier rate of 1 in 21.5.45
The future of population-based carrier screening in Australia There was significant support for prenatal and preconception CF carrier screening by the general community, CF community and health professionals. Only the HGSA has a definitive recommendation about CF. Individuals and couples value screening and carrier couples use the information to make reproductive choices to avoid having a child with CF. Furthermore, individuals and couples value a direct offer of screening from doctors, as uptake is higher when offered in routine settings. However, there are major barriers with regard to offering and accepting population carrier screening for CF, including cost of testing, inequity of access, inaccurate perception that not having a family history of CF lowers risk, time constraints as well as lack of knowledge and available resources for health professionals and no universal standard model of screening in Australia. The CF carrier screening programs in Victoria and New South Wales are small but slowly expanding. Whether the HGSA statement will encourage carrier screening in other states remains to be seen. Greater engagement with obstetricians and GPs is required to expand carrier screening in its current form. There are a number of possibilities for a national CF carrier screening program in Australia. This might be an expansion of the current fee-for-service model, but this does not address equity of access. Government funding for screening would address this issue but it is critical that funding is not only for the cost of the test but also for all services required to provide a screening program, including genetic counselling and prenatal and pre-implantation testing. A more sophisticated model would include a formal program with central governing committee to oversee standards of test delivery and follow-up.
Acknowledgements Author MBD is a consultant to Healthscope Pathology. This study was supported by the Victorian Government’s Operational Infrastructure Support Program.
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