Investigating genomic medicine practice and perceptions amongst Australian non-genetics physicians to inform education and implementation.

Genomic medicine is being implemented on a global scale, requiring a genomic-competent health workforce. To inform education as part of implementation strategies to optimize adoption of genomics by non-genetics physicians, we investigated current practices, perceptions and preferences relating to genomic testing and education. Australian non-genetics physicians completed an online survey; we conducted univariate and multivariate analyses of determinants of confidence and engagement with genomic medicine. Confident or engaged respondents were more likely to be pediatricians, have completed continuing genomics education (CGE) and/or have genomics research experience. Confident or engaged respondents were also more likely to prefer to request genomic testing with support from genetics services than other models. Respondents who had completed CGE and were engaged reported higher confidence than those who were not engaged. We propose a progression of genomic competence aligned with service delivery models, where education is one enabler of mastery or independence to facilitate genomic tests (from referral to requesting with or without clinical genetics support). Workplace learning could provide additional impetus for adoption.

Australian Genomics: Outcomes of a 5-year national program to accelerate the integration of genomics in healthcare.

Australian Genomics is a national collaborative partnership of more than 100 organizations piloting a whole-of-system approach to integrating genomics into healthcare, based on federation principles. In the first five years of operation, Australian Genomics has evaluated the outcomes of genomic testing in more than 5,200 individuals across 19 rare disease and cancer flagship studies. Comprehensive analyses of the health economic, policy, ethical, legal, implementation and workforce implications of incorporating genomics in the Australian context have informed evidence-based change in policy and practice, resulting in national government funding and equity of access for a range of genomic tests. Simultaneously, Australian Genomics has built national skills, infrastructure, policy, and data resources to enable effective data sharing to drive discovery research and support improvements in clinical genomic delivery.

General practitioners' views on genomics, practice and education: A qualitative interview study.

BACKGROUND AND OBJECTIVES: Genomics is moving rapidly into mainstream medicine through clinical genomic testing and consumer-initiated online DNA testing. The aim of this study was to identify Australian general practitioners' (GPs') views on genomics, impact on practice and educational needs to inform continuing education. METHOD: Semi-structured interviews were conducted, with constant comparative inductive analysis and governance from a national taskforce. RESULTS: Twenty-eight GPs (43% female) were interviewed; 71% worked in a metropolitan workplace. Most initially reported little experience with genetic/genomic tests but, when prompted, recognised encountering genomics, mainly non-invasive prenatal and single-gene tests. Many GPs referred patients for cancer screening to genetic services or specialists. GPs reported needing continuing education and resources, with preferences underpinned by relevance to practice. DISCUSSION: GPs are integrating genomic testing into care, mainly through prenatal screening, and anticipate further impact. They want diverse and context-dependent education but are unaware of some available resources, such as The Royal Australian College of General Practitioners' Genomics in general practice guideline.

Measuring physician practice, preparedness and preferences for genomic medicine: a national survey.

OBJECTIVE: Even as genomic medicine is implemented globally, there remains a lack of rigorous, national assessments of physicians' current genomic practice and continuing genomics education needs. The aim of this study was to address this gap. DESIGN: A cross-sectional survey, informed by qualitative data and behaviour change theory, to assess the current landscape of Australian physicians' genomic medicine practice, perceptions of proximity and individual preparedness, and preferred models of practice and continuing education. The survey was advertised nationally through 10 medical colleges, 24 societies, 62 hospitals, social media, professional networks and snowballing. RESULTS: 409 medical specialists across Australia responded, representing 30 specialties (majority paediatricians, 20%), from mainly public hospitals (70%) in metropolitan areas (75%). Half (53%) had contacted their local genetics services and half (54%) had ordered or referred for a gene panel or exome/genome sequencing test in the last year. Two-thirds (67%) think genomics will soon impact their practice, with a significant preference for models that involved genetics services (p<0.0001). Currently, respondents mainly perform tasks associated with pretest family history taking and counselling, but more respondents expect to perform tasks at all stages of testing in the future, including tasks related to the test itself, and reporting results. While one-third (34%) recently completed education in genomics, only a quarter (25%) felt prepared to practise. Specialists would like (more) education, particularly on genomic technologies and clinical utility, and prefer this to be through varied educational strategies. CONCLUSIONS: This survey provides data from a breadth of physician specialties that can inform models of genetic service delivery and genomics education. The findings support education providers designing and delivering education that best meet learner needs to build a competent, genomic-literate workforce. Further analyses are underway to characterise early adopters of genomic medicine to inform strategies to increase engagement.

Ensuring best practice in genomics education and evaluation: reporting item standards for education and its evaluation in genomics (RISE2 Genomics).

PURPOSE: Widespread, quality genomics education for health professionals is required to create a competent genomic workforce. A lack of standards for reporting genomics education and evaluation limits the evidence base for replication and comparison. We therefore undertook a consensus process to develop a recommended minimum set of information to support consistent reporting of design, development, delivery, and evaluation of genomics education interventions. METHODS: Draft standards were derived from literature (25 items from 21 publications). Thirty-six international experts were purposively recruited for three rounds of a modified Delphi process to reach consensus on relevance, clarity, comprehensiveness, utility, and design. RESULTS: The final standards include 18 items relating to development and delivery of genomics education interventions, 12 relating to evaluation, and 1 on stakeholder engagement. CONCLUSION: These Reporting Item Standards for Education and its Evaluation in Genomics (RISE2 Genomics) are intended to be widely applicable across settings and health professions. Their use by those involved in reporting genomics education interventions and evaluation, as well as adoption by journals and policy makers as the expected standard, will support greater transparency, consistency, and comprehensiveness of reporting. Consequently, the genomics education evidence base will be more robust, enabling high-quality education and evaluation across diverse settings.

The expectations and realities of nutrigenomic testing in australia: A qualitative study.

BACKGROUND: Consumer genomic testing for nutrition and wellness, (nutritional genomics), is becoming increasingly popular. Concurrently, health-care practitioners (HPs) working in private practice (including doctors interested in integrative medicine, private genetic counsellors, pharmacists, dieticians, naturopaths and nutritionists) are involved as test facilitators or interpreters. OBJECTIVE: To explore Australian consumers' and HPs' experiences with nutrigenomic testing. METHOD: Semi-structured in-depth interviews were conducted using predominantly purposive sampling. The two data sets were analysed individually, then combined, using a constant comparative, thematic approach. RESULTS: Overall, 45 interviews were conducted with consumers (n = 18) and HPs (n = 27). Many of the consumer interviewees experienced chronic ill-health. Nutrigenomic testing was perceived as empowering and a source of hope for answers. While most made changes to their diet/supplements post-test, self-reported health improvements were small. A positive relationship with their HP appeared to minimize disappointment. HPs' adoption and views of nutrigenomic testing varied. Those enthusiastic about testing saw the possibilities it could offer. However, many felt nutrigenomic testing was not the only 'tool' to utilize when offering health care. DISCUSSION: This research highlights the important role HPs play in consumers' experiences of nutrigenomics. The varied practice suggests relevant HPs require upskilling in this area to at least support their patients/clients, even if nutrigenomic testing is not part of their practice. PATIENT OR PUBLIC CONTRIBUTION: Advisory group included patient/public group representatives who informed study design; focus group participants gave feedback on the survey from which consumer interviewees were sourced. This informed the HP data set design. Interviewees from HP data set assisted with snowball sampling.

Human Genetics Society of Australasia Position Statement: Online DNA Testing.

Increasingly, consumers have been able to seek DNA testing online to explore their personal genetic information. This increased access to a range of genomic tests has raised concerns among health professionals tasked with providing guidance and support to patients requiring genetic/genomic testing. Individuals will seek genomic testing for a range of purposes; equally, the medical marketplace offers a range of different test types. The Human Genetics Society of Australasia (HGSA) published their first statement on Direct to Consumer Genetic Testing (2012 PS02). This is a revised statement, which considers developments in the field of online DNA testing, including rapid technological changes, diversity of applications and decreasing costs of testing. It draws from the first empirical nationwide study (Genioz - Genomics: National Insights of Australians) and insights from consumers with experience of this technology. The rapid adoption of these tests and the broad range of potential consequences have informed perspectives within this statement. It is the position of the HGSA that both individuals/consumers and health care professionals/providers should be supported to make informed choices about online DNA testing. This means adequate and ongoing education and resources should be available for individuals/consumers and health care professionals/providers before, during and after testing. Health care professionals/providers should be appropriately trained, have relevant experience and should be able to demonstrate (or provide evidence of) a current certification in their field of practice. This statement was ratified at the 2018 HGSA Council Meeting and was recently reviewed in 2019 for consistency with other HGSA position statements.

Development of an Evidence-Based, Theory-Informed National Survey of Physician Preparedness for Genomic Medicine and Preferences for Genomics Continuing Education.

Despite some early implementation of genomic medicine globally, there is a lack of rigorous, large-scale assessments of medical specialists' current practice and continuing education needs. As a first step to addressing this gap, we describe the development of a robust, expert-reviewed, survey using a mixed-methods sequential study design. We conducted semi-structured qualitative interviews with 32 education providers and 86 non-genetic medical specialists about current genomic medicine practice and need for continuing education. Key concepts were identified and used as an initial framework for the survey. These were: personal characteristics (medical specialty, years of practice); current practice of genomics in clinical and research settings; perception of how proximal genomic medicine is to practice; perception of preparedness (competence and confidence); and, preferences for future roles and models of care in genomic medicine and for continuing education. Potential survey questions that related to at least one of these concepts were identified from the literature or were created if no suitable question existed. Using a modified, reactive Delphi approach, questions were reviewed by a panel of 22 experts. Experts were selected purposefully representing four areas of expertise: non-genetic medical specialties; clinical genetics; genetic/genomic education and evaluation; and implementation science. Three Delphi rounds assessed relevance, clarity and importance of each question. The questions were also mapped to the behaviour change wheel theoretical framework which encompasses capability, opportunity and motivation (COM-B). The survey (included as supplementary material) was then tested with a small group of non-genetic medical specialists and feedback was written or verbal in 'talk-aloud', cognitive interviews. The final survey was then piloted with a further 29 specialists. We describe the methodology to create a robust, data- and theory-informed survey. The final survey captures not only levels of experience, practice of genomics and preferences for education but also the challenges around engaging with education. Survey data will provide evidence for education providers to inform development of education which meets learner needs and contributes to a medical workforce that is literate in genomics and more confident to competently practice genomic medicine.

Preparing Medical Specialists for Genomic Medicine: Continuing Education Should Include Opportunities for Experiential Learning.

With the demand for genomic investigations increasing, medical specialists will need to, and are beginning to, practice genomic medicine. The need for medical specialists from diverse specialties to be ready to appropriately practice genomic medicine is widely recognised, but existing studies focus on single specialties or clinical settings. We explored continuing education needs in genomic medicine of a wide range of medical specialists (excluding genetic specialists) from across Australia. Interviews were conducted with 86 medical specialists in Australia from diverse medical specialties. Inductive content analysis categorized participants by career stage and genomics experience. Themes related to education needs were identified through constant comparison and discussion between authors of emerging concepts. Our findings show that participants believe that experiential learning in genomic medicine is necessary to develop the confidence and skills needed for clinical care. The main themes reported are: tailoring of education to the specialty and the individual; peer interactions contextualizes knowledge; experience will aid in developing confidence and skills. In fact, avenues of gaining experience may result in increased engagement with continuing education in genomic medicine as specialists are exposed to relevant applications in their clinical practice. Participants affirmed the need for continuing education in genomic medicine but identified that it would need to be tailored to the specialty and the individual: one size does not fit all, so a multifaceted approached is needed. Participants infrequently attended formal continuing education in genomic medicine. More commonly, they reported experiential learning by observation, case-review or interacting with a "genomics champion" in their specialty, which contextualized their knowledge. Medical specialists anticipate that genomic medicine will become part of their practice which could lessen demand on the specialist genetic workforce. They expect to look to experts within their own medical specialty who have gained genomics expertise for specific and contextualized support as they develop the skills and confidence to practice genomic medicine. These findings highlight the need to include opportunities for experiential learning in continuing education. Concepts identified in these interviews can be tested with a larger sample of medical specialists to ascertain representativeness.

From Expectations to Experiences: Consumer Autonomy and Choice in Personal Genomic Testing.

Background: Personal genomic testing (PGT) offers individuals genetic information about relationships, wellness, sporting ability, and health. PGT is increasingly accessible online, including in emerging markets such as Australia. Little is known about what consumers expect from these tests and whether their reflections on testing resonate with bioethics concepts such as autonomy.Methods: We report findings from focus groups and semi-structured interviews that explored attitudes to and experiences of PGT. Focus group participants had little experience with PGT, while interview participants had undergone testing. Recordings were transcribed and analyzed using thematic analysis. Findings were critically interpreted with reference to bioethics scholarship on autonomy.Results: Fifty-six members of the public participated in seven focus groups, and 40 individuals were interviewed separately. Both groups valued the choice of PGT, and believed that it could motivate relevant actions. Focus group themes centered on the perceived value of choices, knowledge enabling action and knowledge about the self. Interview themes suggest that participants reflexively engage with their PGT information to make meaning, and that some appreciate its shortcomings. Critical interpretation of findings shows that while consumers of PGT are able to exercise a degree of autonomy in choosing, they may not be able to achieve a substantive conceptualization of autonomy, one that promotes alignment with higher-order desires.Conclusions: PGT consumers can critically reason about testing. However, they may uncritically accept test results, may not appreciate drawbacks of increased choice, or may overestimate the potential for information to motivate behavioral change. While consumers appear to be capable of substantive autonomy, they do so without ongoing support from companies. PGT companies promote a problematic ("default") account of autonomy, reliant on empowerment rhetoric. This leaves consumers vulnerable to making decisions inconsistent with their higher-order desires. As PGT expands, claims about its power and value need to be carefully drawn.

Ensuring Best Practice in Genomic Education and Evaluation: A Program Logic Approach.

Targeted genomic education and training of professionals have been identified as core components of strategies and implementation plans for the use of genomics in health care systems. Education needs to be effective and support the sustained and appropriate use of genomics in health care. Evaluation of education programs to identify effectiveness is challenging. Furthermore, those responsible for development and delivery are not necessarily trained in education and/or evaluation. Program logic models have been used to support the development and evaluation of education programs by articulating a logical explanation as to how a program intends to produce the desired outcomes. These are highly relevant to genomic education programs, but do not appear to have been widely used to date. To assist those developing and evaluating genomic education programs, and as a first step towards enabling identification of effective genomic education approaches, we developed a consensus program logic model for genomic education. We drew on existing literature and a co-design process with 24 international genomic education and evaluation experts to develop the model. The general applicability of the model to the development of programs was tested by program convenors across four diverse settings. Conveners reported on the utility and relevance of the logic model across development, delivery and evaluation. As a whole, their feedback suggests that the model is flexible and adaptive across university award programs, competency development and continuing professional development activities. We discuss this program logic model as a potential best practice mechanism for developing genomic education, and to support development of an evaluation framework and consistent standards to evaluate and report genomic education program outcomes and impacts.

Preparing Medical Specialists to Practice Genomic Medicine: Education an Essential Part of a Broader Strategy.

Developing a competent workforce will be crucial to realizing the promise of genomic medicine. The preparedness of medical specialists without specific genetic qualifications to play a role in this workforce has long been questioned, prompting widespread calls for education across the spectrum of medical training. Adult learning theory indicates that for education to be effective, a perceived need to learn must first be established. Medical specialists have to perceive genomic medicine as relevant to their clinical practice. Here, we review what is currently known about medical specialists' perceptions of genomics, compare these findings to those from the genetics era, and identify areas for future research. Previous studies reveal that medical specialists' views on the clinical utility of genomic medicine are mixed and are often tempered by several concerns. Specialists generally perceive their confidence and understanding to be lacking; subsequently, they welcome additional educational support, although specific needs are rarely detailed. Similar findings from the genetics era suggest that these challenges are not necessarily new but on a different scale and relevant to more specialties as genomic applications expand. While existing strategies developed for genetic education and training may be suitable for genomic education and training, investigating the educational needs of a wider range of specialties is critically necessary to determine if tailored approaches are needed and, if so, to facilitate these. Other interventions are also required to address some of the additional challenges identified in this review, and we encourage readers to see education as part of a broader implementation strategy.

Lessons learnt from implementing change in newborn bloodspot screening processes over more than a decade: Midwives, genetics and education.

OBJECTIVE: To explore midwives' roles and education requirements in newborn bloodspot screening (NBS) for genetic conditions, as programs and supporting education evolve over time. BACKGROUND: NBS processes are evolving and will continue to evolve with new genetic and genomic technologies. Midwives have a critical role in facilitating NBS, as they are the primary healthcare professional to interact with parents at the time of collecting the bloodspot. As new consent processes and genomic technologies are incorporated into NBS, midwives need to stay up-to-date with these changes, so that parents can make an informed decision about having the test and future use of the DNA sample. RESEARCH DESIGN/SETTING: We used a cross-sectional approach to analyse midwives' knowledge and behaviour in 2005/6 and 2016, with changes in NBS processes and education introduced in 2011. FINDINGS: We found midwives' NBS knowledge improved in 8/18 areas after a 10-year period, mostly related to process changes, but there was also an increase in misconceptions regarding which conditions are screened. Areas of significant improvement were not consistently explained by participation in continuing professional development (CPD). We found midwives used official brochures and NBS collection cards to guide discussions with families. Changes to the NBS collection cards, together with the content of CPD materials, aligned with the significant improvements and deficits we observed. When considering potential changes to future maternity care that incorporates emerging genomic technologies, midwives indicated the main barrier was their lack of knowledge; the majority (60.3%) reported supervision support to attend genomics CPD. KEY CONCLUSIONS: Changes in NBS practice should be implemented through multifaceted programs that include education sessions and procedural prompts. The NBS collection card should be seen not just as a legal consent document but also as an educational tool. IMPLICATIONS FOR PRACTICE: As NBS programs evolve through the addition of conditions screened for or changes to technology or consent processes, multiple strategies should be applied to upskill midwives to ensure they can best support parents to make informed choices.

Readiness of clinical genetic healthcare professionals to provide genomic medicine: An Australian census.

We aimed to determine capacity and readiness of Australian clinical genetic healthcare professionals to provide genomic medicine. An online survey was administered to individuals with genetic counseling or clinical genetics qualifications in Australia. Data collected included: education, certification, continuing professional development (CPD), employment, and genetic versus genomic clinical practice. Of the estimated 630 clinical genetic healthcare professionals in Australia, 354 completed the survey (56.2% response rate). Explanatory interviews were conducted with 5.5% of the genetic counselor respondents. Those working clinically reported being involved in aspects of whole exome or genome sequencing (48.6% genetic counselors, 88.6% clinical geneticists). Most genetic counselors (74.2%) and clinical geneticists (87.0%) had attended genomics CPD in the last two years, with 61.0% and 39.1% self-funding, respectively. Genetic counselors desire broad involvement in genomics, including understanding classifying and interpreting results to better counsel patients. The majority of respondents (89.9%) were satisfied with their job and 91.6% planned to work in genetics until retirement. However, 14.1% of the genetic counselors in clinical roles and 24.6% of the clinical geneticists planned to retire within 10 years. This is the first national audit of clinical genetic healthcare professionals, revealing the Australian workforce is motivated and prepared to embrace new models to deliver genomic medicine but consideration of education and training is required to meet demand.

Personal genomic testing for nutrition and wellness in Australia: A content analysis of online information.

AIM: Personal genomic testing for nutrition and wellness (PGT-NG) offers a new service delivery model to nutritionists and dietitians. However, research indicates that this type of testing currently lacks sufficient clinical validity and utility to be commercially available. Despite Australian guidelines to the contrary, healthcare professionals are currently offering testing to clients, and promoting these services online. Thus, it is important to understand how PGT-NG is currently framed online to the public. METHODS: A mixed methods content analysis was conducted to assess the content, quality and marketing approaches of websites offering PGT-NG to Australians. Websites were identified using popular search engines to mimic the behaviour of a consumer. A novel framework was developed for the purposes of the analysis. RESULTS: Thirty-nine websites were analysed, comprising four nutritional genomic testing company websites and 35 healthcare provider websites. Healthcare providers relied on information from the testing companies. The content was emotive, and little attention was given to the scientific and ethical aspects of personal genomic testing. Websites appealed to consumer empowerment and framed testing as an essential and superior tool for optimising health. CONCLUSIONS: Websites lacked the transparency necessary for informed consent. A basic checklist of key information was developed to aid healthcare providers when informing potential clients of PGT-NG online.

Australians' views and experience of personal genomic testing: survey findings from the Genioz study.

Personal genomic tests (PGTs) for multiple purposes are marketed to ostensibly healthy people in Australia. These tests are generally marketed and purchased online commercially or can be ordered through a health professional. There has been minimal engagement with Australians about their interest in and experience with ordering a PGT. As part of a multistage, interdisciplinary project, an online survey (Stage 2 of the Genioz study) was available from May 2016 to May 2017. In total, 3253 respondents attempted the survey, with 2395 completed Australian responses from people with and without experience of having a PGT: 72% were female; 59% of the whole sample were undertaking/or had a university education; and, overall, age ranged from 18-over 80. A total of 571 respondents reported having had a genetic test, 373 of these classifiable as a PGT. A bivariate analysis suggests people who have undergone PGT in our sample were: women aged 25 and over; or in a high socioeconomic group, or have a personal or family diagnosis of a genetic condition (P ≤ 0.03). After a multivariate analysis, socioeconomic status and a genetic condition in the family were not of significance. The most common types of PGT reported were for carrier status and ancestry. Findings suggest greater awareness of, and an increasing demand for non-health related PGT in Australia. To support both consumers and health care professionals with understanding PGT results, there is a need for appropriate support and resources.

Australians' perspectives on support around use of personal genomic testing: Findings from the Genioz study.

Personal genomic testing using direct-to-consumer and consumer-directed models, with or without involvement of healthcare providers, is increasing internationally, including in Australia. This study forms a sub-set of the Genioz study - Genomics: National Insights of Australians. We aimed to explore Australians' experiences with these types of tests, especially online DNA tests, and their views regarding whom they would seek support from around understanding test results. The study used a mixed methods approach, employing an exploratory quantitative online survey and follow-up qualitative semi-structured interviews. Between May 2016 and May 2017, 2841 Australians responded to the survey. Interviews were conducted with 63 purposively sampled respondents, including 45 who had a genetic test and 18 who had not. Of 571 respondents who had any type of genetic test, 322 had a personal genomic test using criteria defined by the researchers. Testing for ancestry/genealogy was the most common, reported by 267 participants, reflecting the increased advertising of these tests in Australia. Some respondents described downloading their raw data for further interpretation through third party websites for genealogical as well as health related information. Carrier testing, testing for serious and preventable conditions and nutrition and/or wellness were the most common health related tests reported by respondents. Participants generally preferred to seek support from general practitioners (GPs), medical specialists with relevant expertise and independent genetics specialists, although another important preference for non-health information was online forums and networks. There was less preference for seeking support from employees associated with the testing companies. Generally, of those who had a health related PGT, the most common actions were seeking medical advice or doing nothing with the information, while more of those who had a personal genomic test for nutrition and/or wellness sought advice from complementary/alternative health practitioners (eg naturopaths) and integrative GPs, and 60% reported they had changed their diet. As awareness of personal genomic testing increases, publicly funded clinical genetics services may be less inclined to discuss results from personal genomic testing. Genetic counsellors could play an important role in providing this support, both pre-test and post-test, through opportunities for private practice but independent from testing companies.

Australians' views on personal genomic testing: focus group findings from the Genioz study.

Personal genomic testing provides healthy individuals with access to information about their genetic makeup for purposes including ancestry, paternity, sporting ability and health. Such tests are available commercially and globally, with accessibility expected to continue to grow, including in Australia; yet little is known of the views/expectations of Australians. Focus groups were conducted within a multi-stage, cross-disciplinary project (Genioz) to explore this. In mid-2015, 56 members of the public participated in seven focus groups, allocated into three age groups: 18-24, 25-49, and ≥50 years. Three researchers coded transcripts independently and generated themes. Awareness of personal genomic testing was low, but most could deduce what "personal genomics" might entail. Very few had heard of the term "direct-to-consumer" testing, which has implications for organisations developing information to support individuals in their decision-making. Participants' understanding of genetics was varied and drawn from several sources. There were diverse perceptions of the relative influence of genetics and environment on health, mental health, behavior, talent, or personality. Views about having a personal genomic test were mixed, with greater interest in health-related tests if they believed there was a reason for doing so. However, many expressed scepticisms about the types of tests available, and how the information might be used; concerns were also raised about privacy and the potential for discrimination. These exploratory findings inform subsequent stages of the Genioz study, thereby contributing to strategies of supporting Australians to understand and make meaningful and well-considered decisions about the benefits, harms, and implications of personal genomic tests.

FMR1 allele size distribution in 35,000 males and females: a comparison of developmental delay and general population cohorts.

PURPOSE: Developmental delay phenotypes have been associated with FMR1 premutation (PM: 55-200 CGG repeats) and "gray zone" (GZ: 45-54 CGG repeats) alleles. However, these associations have not been confirmed by larger studies to be useful in pediatric diagnostic or screening settings. METHODS: This study determined the prevalence of PM and GZ alleles in two independent cohorts of 19,076 pediatric referrals to developmental delay diagnostic testing through Victorian Clinical Genetics Service (cohort 1: N = 10,235; cohort 2: N = 8841), compared with two independent general population cohorts (newborn screening N = 1997; carrier screening by the Victorian Clinical Genetics Service prepair program N = 14,249). RESULTS: PM and GZ prevalence rates were not significantly increased (p > 0.05) in either developmental delay cohort (male PM: 0.12-0.22%; female PM: 0.26-0.33%; male GZ: 0.68-0.69%; female GZ: 1.59-2.13-%) compared with general population cohorts (male PM: 0.20%; female PM: 0.27-0.82%; male GZ: 0.79%; female GZ: 1.43-2.51%). Furthermore, CGG size distributions were comparable across datasets, with each having a modal value of 29 or 30 and ~1/3 females and ~1/5 males having at least one allele with ≤26 CGG repeats. CONCLUSION: These data do not support the causative link between PM and GZ expansions and developmental-delay phenotypes in pediatric settings.