Reproductive genetic screening
thesisposted on 31.05.2017, 06:14 by Ioannou, Liane Julia
Aim: The aims of this thesis were to explore the characteristics of individuals who accepted, declined or were not offered cystic fibrosis (CF) carrier screening and the outcomes of reproductive genetic screening through the evaluation of two separate carrier screening programs in Victoria, Australia. Research Projects: 1. Multi-disease carrier screening program in Jewish high schools Background/Aim: A screening program for Tay Sachs disease (TSD) carrier status was introduced in high schools in Victoria in 1997, and was expanded to screen for six other genetic conditions common in the Ashkenazi Jewish population in 2008. The aim of this questionnaire-based study was to evaluate the current program and compare it with an evaluation of the program when screening was offered for TSD alone. Methods: All students, in the second last year of high school, who were offered multi-condition carrier screening were invited to participate in the study. Results/Conclusion: This study found that knowledge levels were decreased and predictive negative feelings if found to be a carrier increased, compared to the previous study when only TSD screening was offered. 2. Carrier couples identified through the Genetic Health Services Victoria CF carrier screening program Background/Aim: In 2006 a population-based CF carrier screening program was implemented in Victoria by Genetic Health Services Victoria (GHSV). Screening is offered to pregnant women and couples planning a pregnancy by private obstetricians and general practitioners for a cost of $220 for each test. The aim of this study was to explore the experiences of couples who were both identified as carriers of CF. Methods: Between January 2006 and December 2010, 10 carrier couples were identified, and all were invited to participate in the study. A total of nine interviews were conducted, seven couple interviews and two individual interviews, and 12 completed questionnaires were received. Results/Conclusions: The results of the interview-based study indicated that couples were shocked and were unprepared for a positive carrier couple result. All couples changed their reproductive behaviour as a result of their carrier couple status and informed family members of their increased risk. The results of the questionnaire-based study were compared to a previous evaluation of the program exploring the attitudes and outcomes of CF screening for carriers and non-carriers. It was found that carrier couples have a high knowledge of CF and screening and there is no difference in knowledge between carrier couples and carriers, however both groups have a significantly higher knowledge than non-carriers. No carrier couples regretted having screening, with all saying that if they had their time again they would still have CF carrier screening. 3. Pregnant women who declined CF carrier screening Background/Aim: CF carrier screening is currently offered to women during the early stages of pregnancy and couples planning a pregnancy by private obstetricians and general practitioners. The aim of this study was to assess the attitudes of women declining an offer of screening and to compare these to the attitudes of individuals who accepted an offer of screening. Methods: Pregnant women who were offered CF carrier screening through the GHSV program and declined the offer were recruited at ultrasound and obstetric clinics and invited to participate in this questionnaire-based study. Results/Conclusion: There was no difference in demographics between those who declined and those who accepted an offer of screening. However, knowledge levels were significantly lower in those who declined screening compared to those who accepted it (carrier couples, carriers and non-carriers). The main reason for declining an offer of screening was lack of family history of CF. 4. Pregnant women who were not offered CF carrier screening Background/Aim: Carrier screening for CF is currently only offered in the private health system in Victoria. The aim of this study was to determine the attitudes of pregnant women who did not receive an offer of CF carrier screening, towards carrier screening for CF and compare it to those who were offered screening. Methods: Participants were recruited at antenatal clinics at two public hospitals and were invited to participate in this questionnaire-based study. Results/Conclusion: Those who were not offered screening were significantly younger, had a lower level of education and lower income compared to those who were offered screening. Knowledge of CF and screening was significantly lower in those who were not offered screening compared to those who were. Family history is potentially the most influencing factor in the decision whether to have screening. While only half of the participants would have liked to receive an offer of screening during their current pregnancy, the majority believe CF carrier screening should be available to those who wish to have it. Conclusions: As programs expand to screen for more diseases, truly informed consent may not be possible, with the more diseases screened resulting in a decrease in knowledge. Pre-test information should provide basic information on the genetics of recessive conditions which can be applied to all of the diseases screened for, while detailed information should be targeted towards carriers during post-test counselling. As the main reason for declining an offer of CF carrier screening is lack of family history of the disease, pre-test information needs to make clear that most children with recessive conditions have no family history of the condition. The current CF screening program is inequitable as screening is only offered in the private health sector. In order to ensure equity of access, screening needs to be offered in the public health sector with no out-of-pocket expenses, and educational resources and programs need to be developed and targeted towards potential participants.