Carrier screening panels for Ashkenazi Jews: is more better?

Choices, attitudes, and experiences of genetic screening in Latino/a and Ashkenazi Jewish individuals

Genetic screening to inform personal risk has only recently become an option as the cost of sequencing decreases, and our ability to interpret sequence variants improves. Studies have demonstrated that people want to learn about their genetic information and do well after learning it, but minorities are underrepresented in these studies. We surveyed Ashkenazi Jewish (AJ) and Latino/a participants in a genetic screening study to solicit choices about genetic results to return, as well as their experience with learning these results and attitudes about genetic information secrecy and security. Participants had the option to proceed through the study self-guided, and few elected to have traditional pre-test genetic education and counseling. Despite this, the majority were satisfied with the process of selecting and receiving genetic results and felt that they understood their results. Concerns about privacy and confidentiality of genetic data were minimal, though some participants expressed modest concerns about keeping any potential results secret or the confidentiality of their genetic information. Our results support the feasibility of the option of self-guided genetic screening. Additional care will need to be taken when designing population-based screening studies to meet the needs of participants who come from communities with different experiences with genetics.

Coming to terms with the imperfectly normal child: attitudes of Israeli parents of screen-positive infants regarding subsequent prenatal diagnosis

This study examines the interface between newborn screening and prenatal diagnosis from the point-of-view of parents of screen-positive children. Many conditions covered by newborn screening represent classic (autosomal recessive) Mendelian disorders. Parents of screen-positive infants therefore often come to learn that they are carriers of the disease, and face a decision whether to test for it in future pregnancies. Semi-structured interviews were conducted in 2015-2017 with 34 Israeli parents whose child was screen positive. Three major themes emanated from the parents' attitudes toward prenatal testing for the disease in prospective hypothetical pregnancies: rejection of prenatal testing for the disease associated with the screen positive, and relying instead on newborn screening to reveal if a future baby is also sick (18/34, 53%); support of prenatal testing to get more information (7/34, 21%) and support of prenatal testing in order to abort in case of a test positive (9/34, 26%). We discuss the importance of newborn screening for reproductive decision-making, highlighting the arguments associated with positive and negative parental views of the possibility of having another child with the same condition associated with the screen-positive of the child that had already been born. The conclusions challenge the common assertion that parents pursue the dream of the "perfect child" through prenatal diagnosis that "naturally" leads to selective abortion. The diversity of views expressed by Israeli parents of screen-positive children highlights the diversity of normative scripts of "genetic responsibility" in the context of parenthood.

Generating a taxonomy for genetic conditions relevant to reproductive planning

As genome or exome sequencing (hereafter genome-scale sequencing) becomes more integrated into standard care, carrier testing is an important possible application. Carrier testing using genome-scale sequencing can identify a large number of conditions, but choosing which conditions/genes to evaluate as well as which results to disclose can be complicated. Carrier testing generally occurs in the context of reproductive decision-making and involves patient values in a way that other types of genetic testing may not. The Kaiser Permanente Clinical Sequencing Exploratory Research program is conducting a randomized clinical trial of preconception carrier testing that allows participants to select their preferences for results from among broad descriptive categories rather than selecting individual conditions. This paper describes (1) the criteria developed by the research team, the return of results committee (RORC), and stakeholders for defining the categories; (2) the process of refining the categories based on input from patient focus groups and validation through a patient survey; and (3) how the RORC then assigned specific gene-condition pairs to taxonomy categories being piloted in the trial. The development of four categories (serious, moderate/mild, unpredictable, late onset) for sharing results allows patients to select results based on their values without separately deciding their interest in knowing their carrier status for hundreds of conditions. A fifth category, lifespan limiting, was always shared. The lessons learned may be applicable in other results disclosure situations, such as incidental findings.

Designing expanded carrier screening panels: results of a qualitative study with European geneticists

Aim: To explore the views of clinical and molecular geneticists on the inclusion of disorders and specific pathogenic mutations into expanded carrier screening (ECS) tests for reproductive purposes. Materials & methods: In-depth semistructured interviews were conducted with 16 European geneticists between April and September 2014. Results: All participants supported carrier screening for severe, childhood-onset autosomal recessive disorders with known natural history. Some participants were also in favor of screening for late-onset and X-linked disorders. Regarding selection of specific pathogenic mutations, our participants argued that ECS should include highly penetrant pathogenic mutations with known genotype–phenotype associations. Conclusion: This study highlights main challenges surrounding the development of ECS panels and offers suggestions for future research in this rapidly advancing field.

Responsible implementation of expanded carrier screening

This document of the European Society of Human Genetics contains recommendations regarding responsible implementation of expanded carrier screening. Carrier screening is defined here as the detection of carrier status of recessive diseases in couples or persons who do not have an a priori increased risk of being a carrier based on their or their partners' personal or family history. Expanded carrier screening offers carrier screening for multiple autosomal and X-linked recessive disorders, facilitated by new genetic testing technologies, and allows testing of individuals regardless of ancestry or geographic origin. Carrier screening aims to identify couples who have an increased risk of having an affected child in order to facilitate informed reproductive decision making. In previous decades, carrier screening was typically performed for one or few relatively common recessive disorders associated with significant morbidity, reduced life-expectancy and often because of a considerable higher carrier frequency in a specific population for certain diseases. New genetic testing technologies enable the expansion of screening to multiple conditions, genes or sequence variants. Expanded carrier screening panels that have been introduced to date have been advertised and offered to health care professionals and the public on a commercial basis. This document discusses the challenges that expanded carrier screening might pose in the context of the lessons learnt from decades of population-based carrier screening and in the context of existing screening criteria. It aims to contribute to the public and professional discussion and to arrive at better clinical and laboratory practice guidelines.

Differential utilization of expanded genetic screening tests in patients of reproductive ages from private and academic practices

OBJECTIVE

We sought to evaluate the types of genetic screening tests that are performed in women of childbearing ages in New Jersey.

METHOD

Data from patients who had a reproductive genetics consultation between January 1, 2012, and July 31, 2012, were stratified according to the referring providers, i.e., those from academic or private practices, and descriptive analyses performed. Unconventional genetic screening was defined as any test ordered by the referring health care provider outside the recommendations from the American Congress of Obstetricians and Gynecologists or the American College of Medical Genetics and Genomics.

RESULTS

Overall, 30% of 371 patients referred for a genetic consultation underwent unconventional screening. As compared to patients from academic practices, the relative rate of unconventional screening was 10-fold higher among patients from private practices, resulting in a relative 34-fold increase in the estimated cost in genetic screening (P<0.01).

CONCLUSION

This set of preliminary observations highlight the need for further state, nationwide, and international studies to understand the financial, personal, and societal impact that this discrepancy health care system in the use of genetic carrier screening portends.

Do people from the Jewish community prefer ancestry-based or pan-ethnic expanded carrier screening?

Ancestry-based carrier screening in the Ashkenazi Jewish population entails screening for specific autosomal recessive founder mutations, which are rarer among the general population. As it is now technically feasible to screen for many more diseases, the question arises whether this population prefers a limited ancestry-based offer or a pan-ethnic expanded carrier screening panel that goes beyond the diseases that are frequent in their own population, and is offered regardless of ancestry. An online questionnaire was completed by 145 individuals from the Dutch Jewish community (≥18 years) between April and July 2014. In total, 64.8% were aware of the existence of ancestry-based carrier screening, and respondents were generally positive about screening. About half (53.8%) preferred pan-ethnic expanded carrier screening, whereas 42.8% preferred ancestry-based screening. Reasons for preferring pan-ethnic screening included ‘everyone has a right to be tested', ‘fear of stigmatization when offering ancestry-based panels', and ‘difficulties with identifying risk owing to mixed backgrounds'. ‘Preventing high healthcare costs' was the most important reason against pan-ethnic carrier screening among those in favor of an ancestry-based panel. In conclusion, these findings show that people from the Dutch Jewish community have a positive attitude regarding carrier screening in their community for a wide range of diseases. As costs of expanded carrier screening panels are most likely to drop in the near future, it is expected that these panels will receive more support in the future.

Expanded carrier screening in reproductive healthcare: perspectives from genetics professionals

STUDY QUESTION

How do genetics professionals assess the potential benefits and challenges of expanded carrier screening (ECS) in reproductive healthcare?

SUMMARY ANSWER

Genetics professionals believe that current ECS products have major limitations and are not ready for routine use in reproductive healthcare.

WHAT IS KNOWN ALREADY

Non-targeted approaches to carrier screening have been met with uneven enthusiasm from relevant professional organizations. With declining genotyping costs, it is reasonable to expect that the number of genetic conditions evaluated by carrier-screening products will continue to increase. Reproductive healthcare providers will play a critical role in the adoption of ECS and need to be prepared for the potential challenges that lie ahead.

STUDY DESIGN, SIZE, DURATION

Focus groups were convened at six academic medical centers in the USA in March 2011 to examine genetics professionals' views on ECS.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Forty genetic professionals participated in six focus groups for this study. A clinical case report was presented to each focus group to examine participants' opinions about the use of highly multiplexed forms of carrier screening in reproductive healthcare. Focus group transcripts were analyzed for major themes and thematic density across sites using qualitative data analysis software (ATLAS.ti v5.8).

MAIN RESULTS AND THE ROLE OF CHANCE

Participants believed that current ECS products have major limitations pertaining to the analysis of select alleles and genetic mutations. Participants highlighted multiple interpretive and counseling challenges that reproductive healthcare providers may face in communicating ECS results to patients. Participants stressed the importance of communicating these and other limitations to patients before recommending ECS. Participants recommended collaboration with genetic counselors and medical geneticists in providing ECS.

LIMITATIONS, REASONS FOR CAUTION

To the extent that ECS products have not been widely used to date, participants may have had limited familiarity and direct clinical experience with these products. Given that this study was conducted with genetic professionals from academic medical centers in the USA, participant perspectives may not be representative of professional practices and norms in other healthcare settings.

WIDER IMPLICATIONS OF THE FINDINGS

In considering the use of ECS products in their practices, reproductive healthcare providers may find it helpful to consider the perspectives of genetics professionals. These specialists have considerable experience with diverse forms of genetic testing and can provide valuable insights regarding new genomic risk assessment tools such as ECS.

Prenatal healthcare providers' Gaucher disease carrier screening practices

PURPOSE

Gaucher disease carrier screening is controversial in the medical community. The goal of this study was to explore current Gaucher disease carrier screening practices of prenatal healthcare providers.

METHODS

Prenatal healthcare providers were invited by email to complete an electronic-based survey.

RESULTS

A total of 1,454 prenatal healthcare providers, including 209 genetic counselors, 450 midwives, and 795 physicians, completed the study. The majority of genetic counselors (n = 208/209, >99%), physicians (n = 415/450, 92%), and midwives (n = 634/795, 80%) currently offer Jewish ancestry disease carrier screening to couples in whom one or both partners are Jewish. Of providers who offer Jewish ancestry disease screening, the majority of genetic counselors (n = 199/208, 96%) and physicians (n = 352/415, 85%) always or sometimes offer Gaucher disease screening whereas the majority of midwives (n = 357/634, 56%) never offer Gaucher disease screening.

CONCLUSION

This study presents the first report of Gaucher disease carrier screening practices of the prenatal healthcare providers in North America. Our results indicate that Gaucher disease carrier screening is being offered at a high rate within the scope of Jewish ancestry-based carrier screening. This may highlight a need to move away from the debate as to whether Gaucher disease carrier screening should be offered and, instead, focus on how best to provide Gaucher disease carrier screening services.

"The Most Important Test You'll Ever Take"?: attitudes toward confidential carrier matching and open individual testing among modern-religious Jews in Israel

This article reports on attitudes of modern-religious Ashkenazi Jewish adults in Israel toward anonymous carrier matching for severe monogenic diseases by Dor Yesharim (the ultra-orthodox organization) and open individual carrier testing (through a medical center), examining how this important choice is being informed, communicated, made, and reflected on. Qualitative analysis of semi-structured interviews conducted with 23 modern-religious Ashkenazi Jews in 2009-2011 revealed social pressure to utilize Dor Yesharim; however, respondents considered its policy of advising against a marriage between partners who are carriers of the same genetic condition inappropriate for 'love marriages' where a couple's commitment may already be made. Confidential carrier testing was a stepping stone to open carrier testing for those advised not to marry. Respondents varied in their views on when open carrier tests should be conducted. Pre-implantation genetic diagnosis was considered religiously preferable to abortion; however most carrier couples opted for pre-natal testing and selective abortion, challenging stereotypes about the attitudes of religious Jews. It is discussed how carrier screening is contextualized and interpreted not just in terms of religious teachings, but in interaction with lay agency, personal experiences and knowledge of reproductive choices. We conclude by discussing the implications for the social analysis of the ethics of carrier screening in religious communities at risk.

Preconceptional genetic carrier testing and the commercial offer directly-to-consumers

Recently, a number of commercial companies are offering preconceptional carrier tests directly-to-consumers. This offer raises a number of concerns and issues above and beyond those encountered with preconceptional tests offered within the traditional health care setting. In order to bring some of these issues to light and to initiate dialogue on this topic, this article discusses the following issues: the current offer of preconceptional carrier tests (until the end of 2010) through online commercial companies; the implications for the informed consent procedure and the need for good information; the need for medical supervision and follow-up; and the appropriate use of existing resources. The article concludes with some reflections about the potential sustainability of the offer of preconceptional carrier tests directly-to-consumers.

Evaluation of a multi-disease carrier screening programme in Ashkenazi Jewish high schools

A screening programme for Tay Sachs disease (TSD) carrier status was introduced in high schools in Victoria, Australia in 1997, and was expanded to screen for six other genetic conditions common in the Ashkenazi Jewish population in 2008. The aim of this study was to evaluate the current programme and compare it with an evaluation of the programme when screening was offered for TSD alone. All students from Jewish high schools in Melbourne who offered the programme in 2009 were invited to participate in the study. A purpose-designed questionnaire explored the following domains: knowledge (disease and genetics), reasons for screening, anxiety, and predicted negative feelings if found to be a carrier. Two hundred and seventy-three students were offered screening, and 272 (99.6%) completed the questionnaire. Only two students chose not to have screening. Two hundred and seventy-one students were in the penultimate year of high school (99.6%) and 222 were of Ashkenazi Jewish descent (82.5%). The main reasons for choosing screening were the desire to know carrier status and convenience. Knowledge level decreased and negative feelings increased in the current cohort compared to that when screening was offered for TSD alone. We conclude that the current programme is efficient, although increasing the number of conditions resulted in a decrease in knowledge and increase in predicted negative feelings if found to be a carrier of one of the conditions. This has implications for multi-disease screening programmes that will increase in frequency as more conditions can be screened for and costs diminish.

Ashkenazi Jewish screening in the twenty-first century

Ashkenazi Jewish genetic screening has expanded significantly in the past 4 decades. Individuals of Eastern European (Ashkenazi) Jewish (AJ) descent are at increased risk of having offspring with particular genetic diseases that have significant morbidity and mortality. In addition, there are some disorders, such as cystic fibrosis, for which northern European Caucasians are at comparable risk with those of an AJ background. Carrier screening for many of these Jewish genetic disorders has become standard of care. As technology advances, so does the number of disorders for which screening is available. Thus, we need to continue to be cognizant of informed consent, test sensitivity, confidentiality, prenatal diagnosis, preimplantation genetic screening, and public health concerns regarding testing.

Genetic Screening: A Conceptual Framework for Programmes and Policy-Making

Objective

Policy-makers are faced with increasing pressures from a range of different stakeholders to introduce or expand genetic screening programmes. A shared understanding is therefore needed of the many factors influencing these complex policy decisions. Our aim was to develop a theoretical framework that highlights the multiple components and influences involved in genetic screening and the policy-making process.

Methods

As part of a larger research programme, existing policy frameworks relating to genetic screening were identified through a review of the literature. Major themes were identified and synthesized into an overarching framework, which was further refined through discussions with key informants.

Results

The framework consists of three parts. The first part conceptualizes genetic screening as an integrated public health programme. The second part describes the policy-making process at each stage in the life cycle of the programme. The third part depicts the broader context within which policy-making occurs.

Conclusion

This framework can support policy-makers by fostering a common understanding and facilitating dialogue with stakeholders. The framework has also been used as the conceptual foundation for the development of a more elaborate decision-guide.

Preconceptional ancestry-based carrier couple screening for cystic fibrosis and haemoglobinopathies: what determines the intention to participate or not and actual participation?

This paper explores determinants of the intention to participate or not and of actual participation in preconceptional ancestry-based carrier couple screening for cystic fibrosis (CF) and haemoglobinopathies (HbPs). In total, 9453 individuals from a multi-ethnic population were invited. Invitees who had a partner and who were planning a pregnancy were the target population (33-36%). Test participation was conditional on survey participation. Those who refrained from test participation were asked to participate in the survey only. The questionnaire was based on the Theory of Planned Behaviour, which explains behaviour through intention. It was completed by 418 survey participants: 171 who intended to participate in the testing, and 247 who refrained from test participation. Both test intenders and offer decliners generally had a positive attitude towards test participation, and perceived high behavioural control. This applied to Western and non-Western survey participants equally. Offer decliners, however, perceived less control in terms of the time and effort needed for participation. Still, 68% of them intended to participate in the future if the screening would be offered routinely. Test intenders more often would draw reproductive consequences from test results, perceived a higher risk of being a carrier, more benefits and less adverse psychological outcomes. Feelings of stigmatisation were not an important issue, but 14% thought that there would be discrimination against carriers: among them more were non-Western survey participants. Preconceptional ancestry-based CF and HbPs carrier screening was evaluated as positive and desirable among Western and non-Western survey participants. The effort and time needed for participation were important reasons for declining participation, which might be overcome by improving access to the screening.

Population screening for reproductive risk for single gene disorders in Australia: now and the future

Abstract As the results of the Human Genome Project are realized, it has become technically possible to identify carriers of numerous autosomal and X-linked recessive disorders. Couples at risk of having a child with one of these conditions have a number of reproductive options to avoid having a child with the condition should they wish. In Australia the haemoglobinopathies are the only group of conditions for which population screening is widely offered and which is government funded. In some Australian states there are also population screening programs for cystic fibrosis and autosomal recessive conditions more common in Ashkenazi Jewish individuals which are generally offered on a user pays basis. It is predicted that as consumer demand increases and testing becomes cheaper, that many people planning or in the early stages of pregnancy will have carrier screening for multiple genetic conditions. This will have significant implications for genetic counseling, laboratory and prenatal testing resources. In addition such screening raises a number of ethical issues including the value of lives of those born with genetic conditions for which screening is available.

Prevention of lysosomal storage disorders in Israel

Prevention programs for the detection of heterozygotes of relatively prevalent autosomal recessive diseases in various ethnic groups are available in recent years in Israel. Several lysosomal storage disorders (LSD) are included in this program. The goal of the program is the ascertainment of high risk couples before the birth of affected offspring. This is performed by a population screening program that addresses the specific needs and requirements of various population groups in Israel. The programs are supervised and designed by medical/clinical geneticists and are accompanied by genetic counseling prior to and after testing. Three types of population screening programs are in operation. The first type is offered to the general population and is directed to premarital and married couples. High risk families mostly opt for prenatal diagnosis. The second type is performed for diseases with a frequency of about 1:1000. This occurrence is common in Israel only in various Arab communities due to the high rate of consanguinity. The third type is a premarital screening performed by the Orthodox Jewish community and is operated by a nonprofit organization--"Dor Yeshorim". Two heterozygotes for a particular disease are advised not to proceed with the marriage and thus avoid the dilemma of prenatal diagnosis. Founder mutations of the relevant genes for each ethnic group are tested and the testing is tailored for each individual according to his/her ethnic background. Genetic counseling presents family planning options to high risk couples. These programs have resulted in a significant reduction in the birth of affected patients of the tested LSD a well as other recessive diseases in recent years.

Ashkenazi Jews and breast cancer: the consequences of linking ethnic identity to genetic disease

We explored the advantages and disadvantages of using ethnic categories in genetic research. With the discovery that certain breast cancer gene mutations appeared to be more prevalent in Ashkenazi Jews, breast cancer researchers moved their focus from high-risk families to ethnicity. The concept of Ashkenazi Jews as genetically unique, a legacy of Tay-Sachs disease research and a particular reading of history, shaped this new approach even as methodological imprecision and new genetic and historical research challenged it. Our findings cast doubt on the accuracy and desirability of linking ethnic groups to genetic disease. Such linkages exaggerate genetic differences among ethnic groups and lead to unequal access to testing and therapy.

Technical validation of a multiplex platform to detect thirty mutations in eight genetic diseases prevalent in individuals of Ashkenazi Jewish descent

PURPOSE

This study determines the analytic accuracy of a Luminex bead-based commercial analyte-specific reagent for the simultaneous analysis of 30 mutations prevalent in Ashkenazi Jews at eight genetic disease loci.

METHODS

DNA from 20 samples with known abnormal genotypes were run a total of 109 times. DNA from 820 patients with unknown genotypes submitted for Ashkenazi Jewish testing panels were analyzed using our current laboratory techniques. The 820 samples were then stripped of identifiers, coded, and reanalyzed using the Tm Biosciences (Toronto, Canada) Ashkenazi Jewish panel analyte-specific reagent in a blinded fashion. For the controls, comparisons were made with their known genotypes. For the patient samples, the results of the Tm assay were compared with the results of our current assay. For 24 of the 30 mutations, we had genomic DNA controls or detected patients' samples heterozygous for these mutations.

RESULTS

There were no discrepant results in the control or patient samples. In the patient samples, 19,680 genotyping reactions were performed without error in both our laboratory-developed single-disease assays and the Tm multiplex assay. Including the controls, 22,296 genotypes were determined without error.

CONCLUSION

The Tm Biosciences Ashkenazi Jewish analyte-specific reagent is capable of performing accurate analyses of 24 different mutations in eight different genes in a single multiplex reaction and can be used with confidence in the clinical molecular genetics laboratory.