Studying the impact of translational genomic research: Lessons from eMERGE.

Two major goals of the Electronic Medical Record and Genomics (eMERGE) Network are to learn how best to return research results to patient/participants and the clinicians who care for them and also to assess the impact of placing these results in clinical care. Yet since its inception, the Network has confronted a host of challenges in achieving these goals, many of which had ethical, legal, or social implications (ELSIs) that required consideration. Here, we share impediments we encountered in recruiting participants, returning results, and assessing their impact, all of which affected our ability to achieve the goals of eMERGE, as well as the steps we took to attempt to address these obstacles. We divide the domains in which we experienced challenges into four broad categories: (1) study design, including recruitment of more diverse groups; (2) consent; (3) returning results to participants and their health care providers (HCPs); and (4) assessment of follow-up care of participants and measuring the impact of research on participants and their families. Since most phases of eMERGE have included children as well as adults, we also address the particular ELSI posed by including pediatric populations in this research. We make specific suggestions for improving translational genomic research to ensure that future projects can effectively return results and assess their impact on patient/participants and providers if the goals of genomic-informed medicine are to be achieved.

Prospective, multi-site study of healthcare utilization after actionable monogenic findings from clinical sequencing.

As large-scale genomic screening becomes increasingly prevalent, understanding the influence of actionable results on healthcare utilization is key to estimating the potential long-term clinical impact. The eMERGE network sequenced individuals for actionable genes in multiple genetic conditions and returned results to individuals, providers, and the electronic health record. Differences in recommended health services (laboratory, imaging, and procedural testing) delivered within 12 months of return were compared among individuals with pathogenic or likely pathogenic (P/LP) findings to matched individuals with negative findings before and after return of results. Of 16,218 adults, 477 unselected individuals were found to have a monogenic risk for arrhythmia (n = 95), breast cancer (n = 96), cardiomyopathy (n = 95), colorectal cancer (n = 105), or familial hypercholesterolemia (n = 86). Individuals with P/LP results more frequently received services after return (43.8%) compared to before return (25.6%) of results and compared to individuals with negative findings (24.9%; p < 0.0001). The annual cost of qualifying healthcare services increased from an average of $162 before return to $343 after return of results among the P/LP group (p < 0.0001); differences in the negative group were non-significant. The mean difference-in-differences was $149 (p < 0.0001), which describes the increased cost within the P/LP group corrected for cost changes in the negative group. When stratified by individual conditions, significant cost differences were observed for arrhythmia, breast cancer, and cardiomyopathy. In conclusion, less than half of individuals received billed health services after monogenic return, which modestly increased healthcare costs for payors in the year following return.

Returning integrated genomic risk and clinical recommendations: The eMERGE study.

PURPOSE: Assessing the risk of common, complex diseases requires consideration of clinical risk factors as well as monogenic and polygenic risks, which in turn may be reflected in family history. Returning risks to individuals and providers may influence preventive care or use of prophylactic therapies for those individuals at high genetic risk. METHODS: To enable integrated genetic risk assessment, the eMERGE (electronic MEdical Records and GEnomics) network is enrolling 25,000 diverse individuals in a prospective cohort study across 10 sites. The network developed methods to return cross-ancestry polygenic risk scores, monogenic risks, family history, and clinical risk assessments via a genome-informed risk assessment (GIRA) report and will assess uptake of care recommendations after return of results. RESULTS: GIRAs include summary care recommendations for 11 conditions, education pages, and clinical laboratory reports. The return of high-risk GIRA to individuals and providers includes guidelines for care and lifestyle recommendations. Assembling the GIRA required infrastructure and workflows for ingesting and presenting content from multiple sources. Recruitment began in February 2022. CONCLUSION: Return of a novel report for communicating monogenic, polygenic, and family history-based risk factors will inform the benefits of integrated genetic risk assessment for routine health care.

Adolescent Decision-Making Involvement in the Receipt of Genomic Testing Results.

OBJECTIVE: To examine hypothesized predictors of adolescent and parent involvement in the decision about which genomic results to receive. STUDY DESIGN: We conducted a longitudinal cohort study during phase 3 of the electronic Medical Records and Genomics (eMERGE) Network. Dyads reported on how they preferred to make choices (adolescent only, parent only, or jointly). Dyads used a decision tool to choose independently the categories of genetic testing results they wanted. We summarized independent choices, identifying initially discordant dyads. After a facilitated discussion, dyads made a joint decision. Dyads then completed the Decision-Making Involvement Scale (DMIS). We conducted bivariate correlations between DMIS subscale scores and the following hypothesized predictors: adolescent age, preference for adolescent to make their own decision, and discordance on initial independent choices. RESULTS: The sample included 163 adolescents, aged 13-17 years and parents (86.5% mothers). Dyads lacked agreement on how they wanted to make the final decision (weighted kappa statistic 0.04; 95% CI -0.08 to 0.16). These preferences, as well as the adolescent's age and adolescent-parent discordance on initial choices for specific categories of genetic testing results to receive, were associated with subsequent decision-making involvement behaviors as measured by DMIS subscales. Dyads with discordant initial preferences had significantly greater scores on the DMIS Joint/Options subscale than those with concordant initial preferences (adolescent report M [SD] 2.46 [0.60] vs 2.10 [0.68], P < .001). CONCLUSIONS: Through facilitated discussion, adolescents and parents can work together and reach agreement about receipt of genomic screening results.

A mutational hotspot in AMOTL1 defines a new syndrome of orofacial clefting, cardiac anomalies, and tall stature.

AMOTL1 encodes angiomotin-like protein 1, an actin-binding protein that regulates cell polarity, adhesion, and migration. The role of AMOTL1 in human disease is equivocal. We report a large cohort of individuals harboring heterozygous AMOTL1 variants and define a core phenotype of orofacial clefting, congenital heart disease, tall stature, auricular anomalies, and gastrointestinal manifestations in individuals with variants in AMOTL1 affecting amino acids 157-161, a functionally undefined but highly conserved region. Three individuals with AMOTL1 variants outside this region are also described who had variable presentations with orofacial clefting and multi-organ disease. Our case cohort suggests that heterozygous missense variants in AMOTL1, most commonly affecting amino acid residues 157-161, define a new orofacial clefting syndrome, and indicates an important functional role for this undefined region.

Young adults' reasoning for involving a parent in a genomic decision-making research study.

Young adults have increasing genomic testing opportunities; however, little is known about how equipped they feel about making decisions to learn personal genomic information. We conducted qualitative interviews with 19 young adults, ages 18-21 years old, enrolled in a research study where they made decisions about learning personal genomic risk for developing preventable, treatable, and adult-onset conditions and carrier status for autosomal recessive conditions. Participants had the option to include a parent in their study visit and the decision-making process. The goal of this project was to explore young adults' reasons for involving or not involving a parent in the study and to assess young adults' perspectives about parental roles in their healthcare. Nine participants included a parent in the study and ten did not include a parent. Eleven participants received genomic test results before the interview, while eight participants had not yet received their results at the time of the interview. The study team developed a coding guide and coded interview transcripts inductively and deductively using an interpretive descriptive-analytic approach. Logistical issues dominated solo participants' reasons for not involving a parent in the study, whereas those who involved a parent often cited a close relationship with the parent and the parent's previous involvement in the participant's healthcare as reasons for involving them. Both groups of participants described gradually transitioning to independent healthcare decision-making with age and felt their comfort in medical decision-making depends on the severity of and their familiarity with the situation. Participants recommended that future genomic researchers or clinicians give young adults the option to involve a parent or friend as a support person in research or clinical visits. Although young adults may have different journeys toward independent healthcare decision-making, some may benefit from continued parental or peer involvement after reaching the age of legal adulthood.

Multiancestral polygenic risk score for pediatric asthma.

BACKGROUND: Asthma is the most common chronic condition in children and the third leading cause of hospitalization in pediatrics. The genome-wide association study catalog reports 140 studies with genome-wide significance. A polygenic risk score (PRS) with predictive value across ancestries has not been evaluated for this important trait. OBJECTIVES: This study aimed to train and validate a PRS relying on genetic determinants for asthma to provide predictions for disease occurrence in pediatric cohorts of diverse ancestries. METHODS: This study applied a Bayesian regression framework method using the Trans-National Asthma Genetic Consortium genome-wide association study summary statistics to derive a multiancestral PRS score, used one Electronic Medical Records and Genomics (eMERGE) cohort as a training set, used a second independent eMERGE cohort to validate the score, and used the UK Biobank data to replicate the findings. A phenome-wide association study was performed using the PRS to identify shared genetic etiology with other phenotypes. RESULTS: The multiancestral asthma PRS was associated with asthma in the 2 pediatric validation datasets. Overall, the multiancestral asthma PRS has an area under the curve (AUC) of 0.70 (95% CI, 0.69-0.72) in the pediatric validation 1 and AUC of 0.66 (0.65-0.66) in the pediatric validation 2 datasets. We found significant discrimination across pediatric subcohorts of European (AUC, 95% CI, 0.60 and 0.66), African (AUC, 95% CI, 0.61 and 0.66), admixed American (AUC, 0.64 and 0.70), Southeast Asian (AUC, 0.65), and East Asian (AUC, 0.73) ancestry. Pediatric participants with the top 5% PRS had 2.80 to 5.82 increased odds of asthma compared to the bottom 5% across the training, validation 1, and validation 2 cohorts when adjusted for ancestry. Phenome-wide association study analysis confirmed the strong association of the identified PRS with asthma (odds ratio, 2.71, PFDR = 3.71 × 10-65) and related phenotypes. CONCLUSIONS: A multiancestral PRS for asthma based on Bayesian posterior genomic effect sizes identifies increased odds of pediatric asthma.

Reanalysis of eMERGE phase III sequence variants in 10,500 participants and infrastructure to support the automated return of knowledge updates.

PURPOSE: The clinical genomics knowledgebase is dynamic with variant classifications changing as newly identified cases, additional population data, and other evidence become available. This is a challenge for the clinical laboratory because of limited resource availability for variant reassessment. METHODS: Throughout the Electronic Medical Records and Genomics phase III program, clinical sites associated with the Mass General Brigham/Broad sequencing center received automated, real-time notifications when reported variants were reclassified. In this study, we summarized the nature of these reclassifications and described the proactive reassessment framework we used for the Electronic Medical Records and Genomics program data set to identify variants most likely to undergo reclassification. RESULTS: Reanalysis of 1855 variants led to the reclassification of 2% (n = 45) of variants, affecting 0.6% (n = 67) of participants. Of these reclassifications, 78% (n = 35) were high-impact changes affecting reportability, with 8 variants downgraded from likely pathogenic/pathogenic to variants of uncertain significance (VUS) and 27 variants upgraded from VUS to likely pathogenic/pathogenic. Most upgraded variants (67%) were initially classified as VUS-Favor Pathogenic, highlighting the benefit of VUS subcategorization. The most common reason for reclassification was new published case data and/or functional evidence. CONCLUSION: Our results highlight the importance of periodic sequence variant reevaluation and the need for automated approaches to advance routine implementation of variant reevaluations in clinical practice.

The reckoning: The return of genomic results to 1444 participants across the eMERGE3 Network.

PURPOSE: The goal of Electronic Medical Records and Genomics (eMERGE) Phase III Network was to return actionable sequence variants to 25,084 consenting participants from 10 different health care institutions across the United States. The purpose of this study was to evaluate system-based issues relating to the return of results (RoR) disclosure process for clinical grade research genomic tests to eMERGE3 participants. METHODS: RoR processes were developed and approved by each eMERGE institution's internal review board. Investigators at each eMERGE3 site were surveyed for RoR processes related to the participant's disclosure of pathogenic or likely pathogenic variants and engagement with genetic counseling. Standard statistical analysis was performed. RESULTS: Of the 25,084 eMERGE participants, 1444 had a pathogenic or likely pathogenic variant identified on the eMERGEseq panel of 67 genes and 14 single nucleotide variants. Of these, 1077 (74.6%) participants had results disclosed, with 562 (38.9%) participants provided with variant-specific genetic counseling. Site-specific processes that either offered or required genetic counseling in their RoR process had an effect on whether a participant ultimately engaged with genetic counseling (P = .0052). CONCLUSION: The real-life experience of the multiarm eMERGE3 RoR study for returning actionable genomic results to consented research participants showed the impact of consent, method of disclosure, and genetic counseling on RoR.

Experiences of adolescents and their parents after receiving adolescents' genomic screening results.

There has been considerable debate over whether adolescents should have the opportunity to learn genetic information about adult-onset disease risk and carrier status without a clinical indication. Adolescents face increasing opportunities to learn more about such genetic risks through the return of secondary findings from clinical genomic testing, direct-to-consumer genetic testing, and research opportunities. However, little is known about the perspectives of adolescents who have received genomic screening results. We conducted separate qualitative interviews with 15 adolescents and their parents who enrolled in a research protocol where they decided which genomic screening results to receive for the adolescent for up to 32 conditions informed by 84 genes. The goal of these interviews was to explore the impact of adolescents learning genomic results without a clinical indication for screening. Of the participating dyads, four received positive results for a pathogenic/likely pathogenic (P/LP) variant for an autosomal dominant (AD) condition, five received carrier results for a heterozygous P/LP variant for an autosomal recessive (AR) condition, and six received negative results. An interpretive descriptive qualitative approach was used. Interview transcripts were coded using a guide developed by the study team based on themes that emerged from the interviews. Degree of recall and description of results, actionability, and emotional responses differed according to the types of results received. However, all participants were satisfied with their decision to learn results, and most did not report any lasting psychological harms. Participants adapted to genomic information about themselves, even after learning about unexpected increased risk for future health problems. Our findings support the position that, whenever possible, perspectives and wishes of adolescents should be strongly considered and respected in the decision-making process regarding genetic testing.

Do research participants share genomic screening results with family members?

The public health impact of genomic screening can be enhanced by cascade testing. However, cascade testing depends on communication of results to family members. While the barriers and facilitators of family communication have been researched following clinical genetic testing, the factors impacting the dissemination of genomic screening results are unknown. Using the pragmatic Electronic Medical Records and Genomics Network-3 (eMERGE-3) study, we explored the reported sharing practices of participants who underwent genomic screening across the United States. Six eMERGE-3 sites returned genomic screening results for mostly dominant medically actionable disorders and surveyed adult participants regarding communication of results with first-degree relatives. Across the sites, 279 participants completed a 1-month and/or 6-month post-results survey. By 6 months, only 34% of the 156 respondents shared their results with all first-degree relatives and 4% did not share with any. Over a third (39%) first-degree relatives were not notified of the results. Half (53%) of participants who received their results from a genetics provider shared them with all first-degree relatives compared with 11% of participants who received their results from a non-genetics provider. The most frequent reasons for sharing were a feeling of obligation (72%) and that the information could help family members make medical decisions (72%). The most common reasons indicated for not sharing were that the family members were too young (38%), or they were not in contact (25%) or not close to them (25%). These data indicate that the professional returning the results may impact sharing patterns, suggesting that there is a need to continue to educate healthcare providers regarding approaches to facilitate sharing of genetic results within families. Finally, these data suggest that interventions to increase sharing may be universally effective regardless of the origin of the genetic result.

Participant choices for return of genomic results in the eMERGE Network.

PURPOSE: Secondary findings are typically offered in an all or none fashion when sequencing is used for clinical purposes. This study aims to describe the process of offering categorical and granular choices for results in a large research consortium. METHODS: Within the third phase of the electronic MEdical Records and GEnomics (eMERGE) Network, several sites implemented studies that allowed participants to choose the type of results they wanted to receive from a multigene sequencing panel. Sites were surveyed to capture the details of the implementation protocols and results of these choices. RESULTS: Across the ten eMERGE sites, 4664 participants including adolescents and adults were offered some type of choice. Categories of choices offered and methods for selecting categories varied. Most participants (94.5%) chose to learn all genetic results, while 5.5% chose subsets of results. Several sites allowed participants to change their choices at various time points, and 0.5% of participants made changes. CONCLUSION: Offering choices that include learning some results is important and should be a dynamic process to allow for changes in scientific knowledge, participant age group, and individual preference.

Decisional conflict among adolescents and parents making decisions about genomic sequencing results.

Genomic testing of adolescents is increasing yet engaging them in decision-making is not routine. We assessed decisional conflict in adolescents and a parent making independent decisions about actual genomic testing results and factors that influenced their choices. We enrolled 163 dyads consisting of an adolescent (13-17 years) not selected based on a specific clinical indication and one parent. After independently choosing categories of conditions to learn for the adolescent, participants completed the validated Decisional Conflict Scale and a survey assessing factors influencing their respective choices. Adolescents had higher decisional conflict scores than parents (15.6 [IQR:4.7-25.6] vs 9.4 [IQR:1.6-21.9]; P = .0007). Adolescents with clinically significant decisional conflict were less likely to choose to learn all results than adolescents with lower decisional conflict (19.6% vs 80.4%; P < .0001) and less likely to report their choices were influenced by actionability of results (33.3% vs 18.9%; P = .044) and feeling confident they can deal with the results (71.2% vs 91.9%; P = .0005). Our findings suggest higher decisional conflict in adolescents may influence the type and amount of genomic results they wish to learn. Additional research assessing decisional conflict and factors influencing testing choices among adolescents in clinical settings are required.

Using human sequencing to guide craniofacial research.

A recent convergence of technological innovations has re-energized the ability to apply genetics to research in human craniofacial development. Next-generation exome and whole genome sequencing have significantly dropped in price, making it relatively trivial to sequence and analyze patients and families with congenital craniofacial anomalies. A concurrent revolution in genome editing with the use of the CRISPR-Cas9 system enables the rapid generation of animal models, including mouse, which can precisely recapitulate human variants. Here, we summarize the choices currently available to the research community. We illustrate this approach with the study of a family with a novel craniofacial syndrome with dominant inheritance pattern. The genomic analysis suggested a causal variant in AMOTL1 which we modeled in mice. We also made a novel deletion allele of Amotl1. Our results indicate that Amotl1 is not required in the mouse for survival to weaning. Mice carrying the variant identified in the human sequencing studies, however, do not survive to weaning in normal ratios. The cause of death is not understood for these mice complicating our conclusions about the pathogenicity in the index patient. Thus, we highlight some of the powerful opportunities and confounding factors confronting current craniofacial genetic research.

Copb2 is essential for embryogenesis and hypomorphic mutations cause human microcephaly.

Primary microcephaly is a congenital brain malformation characterized by a head circumference less than three standard deviations below the mean for age and sex and results in moderate to severe mental deficiencies and decreased lifespan. We recently studied two children with primary microcephaly in an otherwise unaffected family. Exome sequencing identified an autosomal recessive mutation leading to an amino acid substitution in a WD40 domain of the highly conserved Coatomer Protein Complex, Subunit Beta 2 (COPB2). To study the role of Copb2 in neural development, we utilized genome-editing technology to generate an allelic series in the mouse. Two independent null alleles revealed that Copb2 is essential for early stages of embryogenesis. Mice homozygous for the patient variant (Copb2R254C/R254C) appear to have a grossly normal phenotype, likely due to differences in corticogenesis between the two species. Strikingly, mice heterozygous for the patient mutation and a null allele (Copb2R254C/Zfn) show a severe perinatal phenotype including low neonatal weight, significantly increased apoptosis in the brain, and death within the first week of life. Immunostaining of the Copb2R254C/Zfnbrain revealed a reduction in layer V (CTIP2+) neurons, while the overall cell density of the cortex is unchanged. Moreover, neurospheres derived from animals with Copb2 variants grew less than control. These results identify a general requirement for COPB2 in embryogenesis and a specific role in corticogenesis. We further demonstrate the utility of CRISPR-Cas9 generated mouse models in the study of potential pathogenicity of variants of potential clinical interest.

Genomic education for the next generation of health-care providers.

Historically, medical geneticists and genetic counselors have provided the majority of genetic services. Advances in technology, reduction in testing costs, and increased public awareness have led to a growing demand for genetic services in both clinical and direct-to-consumer spaces. Recent and anticipated changes in the workforce of genetic counselors and medical geneticists require a reexamination of the way we educate health-care providers and the means by which we provide access to genetic services. The time is ripe for rapid growth of genetic and genomic services, but to capitalize on these opportunities, we need to consider a variety of educational mechanisms to reach providers both within and beyond the traditional genetic counseling and medical genetics sectors, including nurses, physician assistants, and nongenetics physicians. This article summarizes the educational efforts underway in each of these professions.

Giving adolescents a voice: the types of genetic information adolescents choose to learn and why.

PURPOSE: The American College of Medical Genetics and Genomics supports parents' opting in or out of secondary analysis of 59 genes when their child has clinical exome/genome sequencing. We explored the reasons adolescents choose to learn certain types of results and the reasons they want to involve or not involve parents in decision-making. METHODS: Adolescents recruited without clinical indication were offered independent, followed by joint choices with a parent to learn genomic results. After making independent choices, adolescent/parent dyads were interviewed to explore the reasons for their choices. Interviews were audio-recorded and transcribed. The constant comparative method was used to analyze 64 purposefully selected transcripts that included 31 from adolescents who excluded some or all potential results. RESULTS: Three major themes informed adolescents' choices: (1) actionability of information, (2) knowledge seeking, and (3) psychological impact. Of adolescents who independently excluded some conditions (n=31), 58% changed their initial choices during the joint interview due to parental influence or improved understanding. Nearly all adolescents (98%) wanted to be involved in the decision-making process, and 53% wanted to make choices independently. CONCLUSIONS: Our findings contribute empirical evidence to support the refinement of professional guidelines for adolescents' engagement and preferences in genetic testing decisions.

Multi-site investigation of strategies for the clinical implementation of CYP2D6 genotyping to guide drug prescribing.

PURPOSE: A number of institutions have clinically implemented CYP2D6 genotyping to guide drug prescribing. We compared implementation strategies of early adopters of CYP2D6 testing, barriers faced by both early adopters and institutions in the process of implementing CYP2D6 testing, and approaches taken to overcome these barriers. METHODS: We surveyed eight early adopters of CYP2D6 genotyping and eight institutions in the process of adoption. Data were collected on testing approaches, return of results procedures, applications of genotype results, challenges faced, and lessons learned. RESULTS: Among early adopters, CYP2D6 testing was most commonly ordered to assist with opioid and antidepressant prescribing. Key differences among programs included test ordering and genotyping approaches, result reporting, and clinical decision support. However, all sites tested for copy-number variation and nine common variants, and reported results in the medical record. Most sites provided automatic consultation and had designated personnel to assist with genotype-informed therapy recommendations. Primary challenges were related to stakeholder support, CYP2D6 gene complexity, phenotype assignment, and sustainability. CONCLUSION: There are specific challenges unique to CYP2D6 testing given the complexity of the gene and its relevance to multiple medications. Consensus lessons learned may guide those interested in pursuing similar clinical pharmacogenetic programs.

Content analysis of requests for religious exemptions from a mandatory influenza vaccination program for healthcare personnel.

OBJECTIVE: Having failed to achieve adequate influenza vaccination rates among employees through voluntary programmes, healthcare organisations have adopted mandatory ones. Some programmes permit religious exemptions, but little is known about who requests religious objections or why. METHODS: Content analysis of applications for religious exemptions from influenza vaccination at a free-standing children's hospital in Cincinnati, Ohio, USA during the 2014-2015 influenza season. RESULTS: Twelve of 15 260 (0.08%) employees submitted applications requesting religious exemptions. Requestors included both clinical and non-clinical employees. All requestors voluntarily identified their religious affiliation, and most were Christian (n=9). Content analysis identified six categories of reasons used to justify an exemption: risks/benefits, ethical/political, lack of direct patient contact, providence, purity and sanctity of life. Individuals articulated reasons in 1-5 (mean 2.6) categories. The most frequently cited category (n=9) was purity; the vaccine and/or its mode of administration were impure, or receiving the vaccine would make the individual impure. Two individuals asserted that the vaccine contained cells derived from aborted human fetuses. Individuals (n=6) also volunteered information supporting the sincerity of their beliefs including distress over previous vaccination and examples of behaviour consistent with their specific objection or their general religious commitment. All requests were approved. CONCLUSIONS: Less than 0.1% of employees requested religious exemptions. Partnering with religious leaders and carefully correcting erroneous information may help address requestors' concerns.

A mutation in FRIZZLED2 impairs Wnt signaling and causes autosomal dominant omodysplasia.

Autosomal dominant omodysplasia is a rare skeletal dysplasia characterized by short humeri, radial head dislocation, short first metacarpals, facial dysmorphism and genitourinary anomalies. We performed next-generation whole-exome sequencing and comparative analysis of a proband with omodysplasia, her unaffected parents and her affected daughter. We identified a de novo mutation in FRIZZLED2 (FZD2) in the proband and her daughter that was not found in unaffected family members. The FZD2 mutation (c.1644G>A) changes a tryptophan residue at amino acid 548 to a premature stop (p.Trp548*). This altered protein is still produced in vitro, but we show reduced ability of this mutant form of FZD2 to interact with its downstream target DISHEVELLED. Furthermore, expressing the mutant form of FZD2 in vitro is not able to facilitate the cellular response to canonical Wnt signaling like wild-type FZD2. We therefore conclude that the FRIZZLED2 mutation is a de novo, novel cause for autosomal dominant omodysplasia.