"Like not having an arm": a qualitative study of the impact of visitor restrictions on cancer care during the COVID-19 pandemic.

PURPOSE: Visitor restriction policies to prevent the spread of COVID-19 among patients and clinicians were widespread during the pandemic, resulting in the exclusion of caregivers at key points of cancer care and treatment decision-making. The aim of this study was to explore how visitor restrictions impacted cancer treatment decision-making and care from patient and physician perspectives. METHODS: Sixty-seven interviews, including 48 cancer patients and 19 cancer and palliative care physicians from four academic cancer centers in the USA between August 2020 and July 2021. RESULTS: Visitor restrictions that prevented caregivers from participating in clinic appointments and perioperative hospital care created challenges in cancer care that spanned three domains: practical, social, and informational. We identified eight themes that characterized challenges within the three domains across all three groups, and that these challenges had negative emotional and psychological consequences for both groups. Physicians perceived that patients' negative experiences due to lack of support through the physical presence of caregivers may have worsened patient outcomes. CONCLUSIONS: Our data demonstrate the tripartite structure of the therapeutic relationship in cancer care with caregivers providing critical support in the decision-making and care process to both patients and physicians. Caregiver absences led to practical, psychosocial, and informational burdens on both groups, and likely increased the risk of burnout among physicians. Our findings suggest that the quality of cancer care can be enhanced by engaging caregivers and promoting their physical presence during clinical encounters.

Genomics Research with Undiagnosed Children: Ethical Challenges at the Boundaries of Research and Clinical Care.

OBJECTIVE: To explore the perspectives of parents of undiagnosed children enrolled in genomic diagnosis research regarding their motivations for enrolling their children, their understanding of the potential burdens and benefits, and the extent to which their experiences ultimately aligned with or diverged from their original expectations. STUDY DESIGN: In-depth interviews were conducted with parents, audio-recorded and transcribed. A structured codebook was applied to each transcript, after which iterative memoing was used to identify themes. RESULTS: Fifty-four parents participated, including 17 (31.5%) whose child received a diagnosis through research. Themes describing parents' expectations and experiences of genomic diagnosis research included (1) the extent to which parents' motivations for participation focused on their hope that it would directly benefit their child, (2) the ways in which parents' frustrations regarding the research process confused the dual clinical and research goals of their participation, and (3) the limited clinical benefits parents ultimately experienced for their children. CONCLUSIONS: Our results suggest that parents of undiagnosed children seeking enrollment in genomic diagnosis research are at risk of a form of therapeutic misconception-in this case, diagnostic misconception. These findings indicate the need to examine the processes and procedures associated with this research to communicate appropriately and balance the potential burdens and benefits of study participation.

Rare Disease, Advocacy and Justice: Intersecting Disparities in Research and Clinical Care.

Rare genetic diseases collectively impact millions of individuals in the United States. These patients and their families share many challenges including delayed diagnosis, lack of knowledgeable providers, and limited economic incentives to develop new therapies for small patient groups. As such, rare disease patients and families often must rely on advocacy, including both self-advocacy to access clinical care and public advocacy to advance research. However, these demands raise serious concerns for equity, as both care and research for a given disease can depend on the education, financial resources, and social capital available to the patients in a given community. In this article, we utilize three case examples to illustrate ethical challenges at the intersection of rare diseases, advocacy and justice, including how reliance on advocacy in rare disease may drive unintended consequences for equity. We conclude with a discussion of opportunities for diverse stakeholders to begin to address these challenges.

Latinx attitudes, barriers, and experiences with genetic counseling and testing: A systematic review.

As genetics is increasingly used across clinical settings, there is a need to understand the impact and experiences of diverse patients. This review systematically examined research literature on Latinx experiences with genetic counseling and genetic testing (GC/GT) in the United States, synthesizing key themes and knowledge gaps pertaining to both patient experience and hypothetical scenarios. Findings were based on a systematic search, inclusion, and thematic analysis of 81 empirical peer-reviewed articles published from January 1990 to July 2019 pertaining to Latinx populations and GC/GT. Studies most commonly addressed Latinas' perspectives on GC/GT in prenatal settings or for hereditary breast and ovarian cancer (HBOC). Costs, referrals, and communication were significant barriers to accessing genetic services for many Latinx patients, particularly those with low English proficiency (LEP). Studies highlighted difficulties accessing and communicating in healthcare settings, and how medical context and prior experience with healthcare workers and institutions influenced GC/GT decision-making. Providers' implicit biases about Latinx patients negatively impacted their care and impeded communication. Despite low awareness of cancer GT, Latinx patients often reported interest in learning more about GC/GT or unmet needs for GT discussion and provider involvement. This systematic review identified areas where providers can take action to improve Latinx experiences with GC/GT. Clinicians should elicit and respond to patient preferences about shared decision-making. For patients with low numeracy or LEP, providers should consider tailored educational and communication techniques. Most studies focused on HBOC and prenatal testing, and Latinx patients are heterogeneous, leaving many research questions about Latinx experience with GT/GC in other clinical areas.

Perceived utility and disutility of genomic sequencing for pediatric patients: Perspectives from parents with diverse sociodemographic characteristics.

Given the limited therapeutic options for most rare diseases diagnosed through genomic sequencing (GS) and the proportion of patients who remain undiagnosed even after GS, it is important to characterize a broader range of benefits and potential harms of GS from the perspectives of families with diverse sociodemographic characteristics. We recruited parents of children enrolled in the Undiagnosed Diseases Network. Parents completed an in-depth interview, and we conducted a comparative content analysis of the data. Parents (n = 30) were demographically diverse, with 43.3% identifying as Hispanic, 33.3% primarily Spanish-speaking, and widely variable household income and education. Parents reported minimal changes in their child's health status following GS but did report a range of other forms of perceived utility, including improvements in their child's healthcare management and access, in their own psychological well-being, and in disease-specific social connections and research opportunities. Parents who received a diagnosis more frequently perceived utility across all domains; however, disutility also was reported by both those with and without a diagnosis. Impacts depended on multiple mediating factors, including parents' underlying expectations and beliefs, family sociodemographic characteristics, individual disease characteristics, and prior healthcare access. Our study suggests that the perceived utility of GS varies widely among parents and may depend on multiple individual, sociodemographic, and contextual factors that are relevant for pre- and post-GS counseling, for value assessment of GS, and for policymaking related to access to new genomic technologies.

Perspectives of Rare Disease Social Media Group Participants on Engaging With Genetic Counselors: Mixed Methods Study.

BACKGROUND: Social media provides a potential avenue for genetic counselors to address gaps in access to reliable genetics information for rare disease communities. However, only limited research has examined patient and family attitudes toward engaging with genetic counselors through social media. OBJECTIVE: Our study assessed the attitudes of members of rare disease social media groups toward engaging with genetic counselors through social media, characteristics associated with greater interest, and the benefits and potential pitfalls of various approaches to such engagement. METHODS: We conducted a mixed methods survey of patients and family members recruited from a systematic sample of rare disease Facebook groups. Patient characteristics and their associations with interest in engagement with genetic counselors were evaluated using univariate and bivariate statistics. Responses to open-ended questions were analyzed using thematic content analysis. RESULTS: In total, 1053 individuals from 103 rare disease groups participated. The median overall interest in engaging with genetic counselors on social media was moderately high at 7.0 (IQR 4.0-9.0, range 0-10). No past experience with a genetic counselor was associated with greater interest in engaging with one through social media (µ=6.5 vs 6.0, P=.04). Participants expressed greatest interest (median 9.0, IQR 5.0-10.0) in engagement models allowing direct communication with genetic counselors, which was corroborated by the majority (n=399, 61.3%) of individuals who responded to open-ended questions explicitly stating their interest in 1-on-1 interactions. When asked what forms of support they would request from genetic counselors through social media, participants desired individualized support and information about how to access services. However, participants also expressed concerns regarding privacy and confidentiality. CONCLUSIONS: Patients and family members in rare disease social media groups appear interested in engaging with genetic counselors through social media, particularly for individualized support. This form of engagement on social media is not meant to replace the current structure and content of genetic counseling (GC) services, but genetic counselors could more actively use social media as a communication tool to address gaps in knowledge and awareness about genetics services and gaps in accessible patient information. Although encouraging, concerns regarding privacy and feasibility require further consideration, pointing to the need for professional guidelines in this area.

Genetic counseling and testing for Asian Americans: a systematic review.

PURPOSE: Asian Americans have been understudied in the literature on genetic and genomic services. The current study systematically identified, evaluated, and summarized findings from relevant qualitative and quantitative studies on genetic health care for Asian Americans. METHODS: A search of five databases (1990 to 2018) returned 8,522 unique records. After removing duplicates, abstract/title screening, and full text review, 47 studies met inclusion criteria. Data from quantitative studies were converted into "qualitized data" and pooled together with thematic data from qualitative studies to produce a set of integrated findings. RESULTS: Synthesis of results revealed that (1) Asian Americans are under-referred but have high uptake for genetic services, (2) linguistic/communication challenges were common and Asian Americans expected more directive genetic counseling, and (3) Asian Americans' family members were involved in testing decisions, but communication of results and risk information to family members was lower than other racial groups. CONCLUSION: This study identified multiple barriers to genetic counseling, testing, and care for Asian Americans, as well as gaps in the research literature. By focusing on these barriers and filling these gaps, clinical genetic approaches can be tailored to meet the needs of diverse patient groups, particularly those of Asian descent.

Opportunities and pitfalls of social media research in rare genetic diseases: a systematic review.

PURPOSE: Social media may be particularly valuable in research in rare genetic diseases because of the low numbers of patients and the rare disease community's robust online presence. The goal of this systematic review was to understand how social media is currently used in rare disease research and the characteristics of the participants in these studies. METHODS: We conducted a systematic review of six databases to identify studies published in English between January 2004 and November 2020, of which 120 met inclusion criteria. RESULTS: Most studies were observational (n = 114, 95.0%) and cross-sectional (n = 107, 89.2%), and more than half (n = 69, 57.5%) utilized only surveys. Only 101 rare diseases were included across all studies. Participant demographics, when reported, were predominantly female (70.1% ± 22.5%) and white (85.0% ± 11.0%) adult patients and caregivers. CONCLUSION: Despite its potential benefits in rare disease research, the use of social media is still methodologically limited and the participants reached may not be representative of the rare disease population by gender, race, age, or rare disease type. As scholars explore using social media for rare disease research, careful attention should be paid to representativeness when studying this diverse patient community.

"It seems like COVID-19 now is the only disease present on Earth": living with a rare or undiagnosed disease during the COVID-19 pandemic.

PURPOSE: Patients with rare and undiagnosed diseases (RUDs) face significant health challenges, which may be exacerbated during the COVID-19 pandemic. The goal of this study was to identify specific impacts of the pandemic on RUD patients, and targets for improving support and health-care access. METHODS: We conducted an online survey of RUD patients and their family members from 21 April to 8 June 2020, recruited from 76 Facebook groups for RUDs. Questions assessed patient characteristics and impacts of the pandemic on RUD diagnosis and management. RESULTS: Respondents (n = 413), including 274 RUD patients and 139 family members, were predominantly female and white, though income varied. Impacts of the pandemic included (1) barriers to accessing essential health care, (2) specific impacts of restrictive COVID-19 visitation policies on ability to advocate in health-care settings, (3) uncertainty and fear regarding COVID-19 risk, (4) exacerbated physical and mental health challenges, (5) magnified impacts of reduced educational and therapeutic services, and (6) unexpected positive changes due to the pandemic. CONCLUSION: There are specific, serious challenges affecting RUD patients and families during the COVID-19 pandemic. There is an urgent need to develop approaches to mitigate these challenges both during and beyond the pandemic.

"Doctors can read about it, they can know about it, but they've never lived with it": How parents use social media throughout the diagnostic odyssey.

Parents of children with undiagnosed conditions struggle to obtain information about how to treat and support their children. It can be particularly challenging to find communities and other parents who share their experiences and can provide emotional and informational support. This study sought to characterize how parents use social media, both throughout the diagnostic odyssey and post-diagnosis, to meet their informational, social, and emotional support needs. We conducted qualitative semi-structured interviews with 14 parents from the Stanford site of the Undiagnosed Diseases Network (UDN), including five whose children had received a diagnosis through study participation. Interview recordings were analyzed using inductive, team-based coding and thematic analysis based in grounded theory using Dedoose qualitative analysis software. Through this process, we identified four key themes related to social media use. First, parents struggled to find the "right" community, often seeking out groups of similar patients based on symptoms or similar conditions. Second, though they found much valuable information through social media about caring for their child, they also struggled to interpret the relevance of the information to their own child's condition. Third, the social support and access to other patients' and families' lived experiences were described as both highly valued and emotionally challenging, particularly in the case of poor outcomes for similar families. Finally, parents expressed the need to balance concerns about their child's privacy with the value of transparency and data sharing for diagnosis. Our results suggest that the needs and experiences of undiagnosed patients and families differ from those with diagnosed diseases and highlight the need for support in best utilizing social media resources at different stages of the diagnostic odyssey.

Ventilator Triage Policies During the COVID-19 Pandemic at U.S. Hospitals Associated With Members of the Association of Bioethics Program Directors.

BACKGROUND: The coronavirus disease 2019 pandemic has or threatens to overwhelm health care systems. Many institutions are developing ventilator triage policies. OBJECTIVE: To characterize the development of ventilator triage policies and compare policy content. DESIGN: Survey and mixed-methods content analysis. SETTING: North American hospitals associated with members of the Association of Bioethics Program Directors. PARTICIPANTS: Program directors. MEASUREMENTS: Characteristics of institutions and policies, including triage criteria and triage committee membership. RESULTS: Sixty-seven program directors responded (response rate, 91.8%); 36 (53.7%) hospitals did not yet have a policy, and 7 (10.4%) hospitals' policies could not be shared. The 29 institutions providing policies were relatively evenly distributed among the 4 U.S. geographic regions (range, 5 to 9 policies per region). Among the 26 unique policies analyzed, 3 (11.3%) were produced by state health departments. The most frequently cited triage criteria were benefit (25 policies [96.2%]), need (14 [53.8%]), age (13 [50.0%]), conservation of resources (10 [38.5%]), and lottery (9 [34.6%]). Twenty-one (80.8%) policies use scoring systems, and 20 of these (95.2%) use a version of the Sequential Organ Failure Assessment score. Among the policies that specify the triage team's composition (23 [88.5%]), all require or recommend a physician member, 20 (87.0%) a nurse, 16 (69.6%) an ethicist, 8 (34.8%) a chaplain, and 8 (34.8%) a respiratory therapist. Thirteen (50.0% of all policies) require or recommend that those making triage decisions not be involved in direct patient care, but only 2 (7.7%) require that their decisions be blinded to ethically irrelevant considerations. LIMITATION: The results may not be generalizable to institutions without academic bioethics programs. CONCLUSION: Over one half of respondents did not have ventilator triage policies. Policies have substantial heterogeneity, and many omit guidance on fair implementation. PRIMARY FUNDING SOURCE: None.

Patient and family social media use surrounding a novel treatment for a rare genetic disease: a qualitative interview study.

PURPOSE: Advances in gene therapy and precision medicine have led to a growing number of novel treatments for rare genetic diseases. Patients/families may lack access to up-to-date, accurate, and relevant information about these treatments. Social media offers one potentially important resource for these communities. Our goal was to understand how patients/families with spinal muscular atrophy (SMA)-a rare genetic condition-used social media to share, consume, and evaluate information about the novel treatment nusinersen (Spinraza) following the drug's approval. METHODS: We conducted qualitative, semistructured interviews with 20 SMA patients or parents of patients, deriving themes and subthemes through content and thematic network analysis. Participants also completed a demographic survey. RESULTS: Participants described leveraging social media to learn about nusinersen treatment, make informed treatment decisions, and advocate for/access treatment. They also described critically evaluating the trustworthiness of nusinersen-related information on social media and the privacy risks of social media use. CONCLUSION: Patients/families used social media to navigate the new and dynamic landscape of nusinersen treatment for SMA, while attempting to mitigate misinformation and privacy risks. As new treatments become available, providers and patients/families may benefit from proactively discussing social media use, so as to maximize important benefits while minimizing risks.

Assessing genetic counselors' experiences with physician aid-in-dying and practice implications.

Physician aid-in-dying (PAD) is now legalized in more than half a dozen states across the United States yet remains controversial among health care providers and the general public. Previous studies have described physicians' and nurses' experiences with and attitudes about PAD; however, there is no data about PAD in the context of genetic counseling. This study explores genetic counselors' experiences, understanding, training, and perspectives about PAD. Fifteen participants were recruited to complete semistructured telephone interviews. Five participants had received patient inquiries about PAD. Most participants (n = 10) did not feel prepared to discuss PAD with patients and felt that they did not have adequate knowledge to answer patient questions about the practice. Participants described how the unique training, skills, and experiences of genetic counselors could be beneficial for discussing PAD with patients, in comparison to other providers. All participants supported training for genetic counselors about PAD, with many suggesting integration with education about palliative care and end-of-life planning. This is the first study to investigate PAD in the context of genetic counseling. Genetic counselors have had patients ask questions about PAD, want education and access to resources about PAD, and believe they can provide important support and guidance to patients considering PAD in some genetic counseling contexts.

The Genetic Basis of Mendelian Phenotypes: Discoveries, Challenges, and Opportunities.

Discovering the genetic basis of a Mendelian phenotype establishes a causal link between genotype and phenotype, making possible carrier and population screening and direct diagnosis. Such discoveries also contribute to our knowledge of gene function, gene regulation, development, and biological mechanisms that can be used for developing new therapeutics. As of February 2015, 2,937 genes underlying 4,163 Mendelian phenotypes have been discovered, but the genes underlying ∼50% (i.e., 3,152) of all known Mendelian phenotypes are still unknown, and many more Mendelian conditions have yet to be recognized. This is a formidable gap in biomedical knowledge. Accordingly, in December 2011, the NIH established the Centers for Mendelian Genomics (CMGs) to provide the collaborative framework and infrastructure necessary for undertaking large-scale whole-exome sequencing and discovery of the genetic variants responsible for Mendelian phenotypes. In partnership with 529 investigators from 261 institutions in 36 countries, the CMGs assessed 18,863 samples from 8,838 families representing 579 known and 470 novel Mendelian phenotypes as of January 2015. This collaborative effort has identified 956 genes, including 375 not previously associated with human health, that underlie a Mendelian phenotype. These results provide insight into study design and analytical strategies, identify novel mechanisms of disease, and reveal the extensive clinical variability of Mendelian phenotypes. Discovering the gene underlying every Mendelian phenotype will require tackling challenges such as worldwide ascertainment and phenotypic characterization of families affected by Mendelian conditions, improvement in sequencing and analytical techniques, and pervasive sharing of phenotypic and genomic data among researchers, clinicians, and families.

De novo mutations in NALCN cause a syndrome characterized by congenital contractures of the limbs and face, hypotonia, and developmental delay.

Freeman-Sheldon syndrome, or distal arthrogryposis type 2A (DA2A), is an autosomal-dominant condition caused by mutations in MYH3 and characterized by multiple congenital contractures of the face and limbs and normal cognitive development. We identified a subset of five individuals who had been putatively diagnosed with "DA2A with severe neurological abnormalities" and for whom congenital contractures of the limbs and face, hypotonia, and global developmental delay had resulted in early death in three cases; this is a unique condition that we now refer to as CLIFAHDD syndrome. Exome sequencing identified missense mutations in the sodium leak channel, non-selective (NALCN) in four families affected by CLIFAHDD syndrome. We used molecular-inversion probes to screen for NALCN in a cohort of 202 distal arthrogryposis (DA)-affected individuals as well as concurrent exome sequencing of six other DA-affected individuals, thus revealing NALCN mutations in ten additional families with "atypical" forms of DA. All 14 mutations were missense variants predicted to alter amino acid residues in or near the S5 and S6 pore-forming segments of NALCN, highlighting the functional importance of these segments. In vitro functional studies demonstrated that NALCN alterations nearly abolished the expression of wild-type NALCN, suggesting that alterations that cause CLIFAHDD syndrome have a dominant-negative effect. In contrast, homozygosity for mutations in other regions of NALCN has been reported in three families affected by an autosomal-recessive condition characterized mainly by hypotonia and severe intellectual disability. Accordingly, mutations in NALCN can cause either a recessive or dominant condition characterized by varied though overlapping phenotypic features, perhaps based on the type of mutation and affected protein domain(s).

Pathways from autism spectrum disorder diagnosis to genetic testing.

PURPOSE: This study examined challenges faced by families and health providers related to genetic testing for autism spectrum disorder (ASD). METHODS: This qualitative study of 14 parents and 15 health providers identified an unstandardized three-step process for families who pursue ASD genetic testing. RESULTS: Step 1 is the clinical diagnosis of ASD, confirmed by providers practicing alone or in a team. Step 2 is the offer of genetic testing to find an etiology. For those offered testing, step 3 involves the parents' decision whether to pursue testing. Despite professional guidelines and recommendations, interviews describe considerable variability in approaches to genetic testing for ASD, a lack of consensus among providers, and questions about clinical utility. Many families in our study were unaware of the option for genetic testing; testing decisions by parents appear to be influenced by both provider recommendations and insurance coverage. CONCLUSION: Consideration of genetic testing for ASD should take into account different views about the clinical utility of testing and variability in insurance coverage. Ideally, policy makers from the range of clinical specialties involved in ASD care should revisit policies to clarify the purpose of genetic testing for ASD and promote consensus about its appropriate use.

Exome Sequencing of Phenotypic Extremes Identifies CAV2 and TMC6 as Interacting Modifiers of Chronic Pseudomonas aeruginosa Infection in Cystic Fibrosis.

Discovery of rare or low frequency variants in exome or genome data that are associated with complex traits often will require use of very large sample sizes to achieve adequate statistical power. For a fixed sample size, sequencing of individuals sampled from the tails of a phenotype distribution (i.e., extreme phenotypes design) maximizes power and this approach was recently validated empirically with the discovery of variants in DCTN4 that influence the natural history of P. aeruginosa airway infection in persons with cystic fibrosis (CF; MIM219700). The increasing availability of large exome/genome sequence datasets that serve as proxies for population-based controls affords the opportunity to test an alternative, potentially more powerful and generalizable strategy, in which the frequency of rare variants in a single extreme phenotypic group is compared to a control group (i.e., extreme phenotype vs. control population design). As proof-of-principle, we applied this approach to search for variants associated with risk for age-of-onset of chronic P. aeruginosa airway infection among individuals with CF and identified variants in CAV2 and TMC6 that were significantly associated with group status. These results were validated using a large, prospective, longitudinal CF cohort and confirmed a significant association of a variant in CAV2 with increased age-of-onset of P. aeruginosa airway infection (hazard ratio = 0.48, 95% CI=[0.32, 0.88]) and variants in TMC6 with diminished age-of-onset of P. aeruginosa airway infection (HR = 5.4, 95% CI=[2.2, 13.5]) A strong interaction between CAV2 and TMC6 variants was observed (HR=12.1, 95% CI=[3.8, 39]) for children with the deleterious TMC6 variant and without the CAV2 protective variant. Neither gene showed a significant association using an extreme phenotypes design, and conditions for which the power of an extreme phenotype vs. control population design was greater than that for the extreme phenotypes design were explored.

Attitudes of genetics professionals toward the return of incidental results from exome and whole-genome sequencing.

Professional recommendations for the return of results from exome and whole-genome sequencing (ES/WGS) have been controversial. The lack of clear guidance about whether and, if so, how to return ES/WGS incidental results limits the extent to which individuals and families might benefit from ES/WGS. The perspectives of genetics professionals, particularly those at the forefront of using ES/WGS in clinics, are largely unknown. Data on stakeholder perspectives could help clarify how to weigh expert positions and recommendations. We conducted an online survey of 9,857 genetics professionals to learn their attitudes on the return of incidental results from ES/WGS and the recent American College of Medical Genetic and Genomics Recommendations for Reporting of Incidental Findings in Clinical Exome and Genome Sequencing. Of the 847 respondents, 760 completed the survey. The overwhelming majority of respondents thought that incidental ES/WGS results should be offered to adult patients (85%), healthy adults (75%), and the parents of a child with a medical condition (74%). The majority thought that incidental results about adult-onset conditions (62%) and carrier status (62%) should be offered to the parents of a child with a medical condition. About half thought that offered results should not be limited to those deemed clinically actionable. The vast majority (81%) thought that individual preferences should guide return. Genetics professionals' perspectives on the return of ES/WGS results differed substantially from current recommendations, underscoring the need to establish clear purpose for recommendations on the return of incidental ES/WGS results as professional societies grapple with developing and updating recommendations.

Pathogenic variants for Mendelian and complex traits in exomes of 6,517 European and African Americans: implications for the return of incidental results.

Exome sequencing (ES) is rapidly being deployed for use in clinical settings despite limited empirical data about the number and types of incidental results (with potential clinical utility) that could be offered for return to an individual. We analyzed deidentified ES data from 6,517 participants (2,204 African Americans and 4,313 European Americans) from the National Heart, Lung, and Blood Institute Exome Sequencing Project. We characterized the frequencies of pathogenic alleles in genes underlying Mendelian conditions commonly assessed by newborn-screening (NBS, n = 39) programs, genes associated with age-related macular degeneration (ARMD, n = 17), and genes known to influence drug response (PGx, n = 14). From these 70 genes, we identified 10,789 variants and curated them by manual review of OMIM, HGMD, locus-specific databases, or primary literature to a total of 399 validated pathogenic variants. The mean number of risk alleles per individual was 15.3. Every individual had at least five known PGx alleles, 99% of individuals had at least one ARMD risk allele, and 45% of individuals were carriers for at least one pathogenic NBS allele. The carrier burden for severe recessive childhood disorders was 0.57. Our results demonstrate that risk alleles of potential clinical utility for both Mendelian and complex traits are detectable in every individual. These findings highlight the necessity of developing guidelines and policies that consider the return of results to all individuals and underscore the need to develop innovative approaches and tools that enable individuals to exercise their choice about the return of incidental results.

Mutations in PIEZO2 cause Gordon syndrome, Marden-Walker syndrome, and distal arthrogryposis type 5.

Gordon syndrome (GS), or distal arthrogryposis type 3, is a rare, autosomal-dominant disorder characterized by cleft palate and congenital contractures of the hands and feet. Exome sequencing of five GS-affected families identified mutations in piezo-type mechanosensitive ion channel component 2 (PIEZO2) in each family. Sanger sequencing revealed PIEZO2 mutations in five of seven additional families studied (for a total of 10/12 [83%] individuals), and nine families had an identical c.8057G>A (p.Arg2686His) mutation. The phenotype of GS overlaps with distal arthrogryposis type 5 (DA5) and Marden-Walker syndrome (MWS). Using molecular inversion probes for targeted sequencing to screen PIEZO2, we found mutations in 24/29 (82%) DA5-affected families and one of two MWS-affected families. The presence of cleft palate was significantly associated with c.8057G>A (Fisher's exact test, adjusted p value < 0.0001). Collectively, although GS, DA5, and MWS have traditionally been considered separate disorders, our findings indicate that they are etiologically related and perhaps represent variable expressivity of the same condition.