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Purpose: We compared the rate of errors in genome sequencing (GS) result disclosures by genetic counselors (GC) and trained non-genetics healthcare professionals (NGHPs) in SouthSeq, a randomized trial utilizing GS in critically ill infants., Methods: Over 400 recorded GS result disclosures were analyzed for major and minor errors. We used Fisher's exact test to compare error rates between GCs and NGHPs and performed a qualitative content analysis to characterize error themes., Results: Major errors were identified in 7.5% of disclosures by NGHPs and in no disclosures by GCs. Minor errors were identified in 32.1% of disclosures by NGHPs and in 11.4% of disclosures by GCs. Although most disclosures lacked errors, NGHPs were significantly more likely to make any error than GCs for all result types (positive, negative, or uncertain). Common major error themes include omission of critical information, overstating a negative result, and overinterpreting an uncertain result. The most common minor error was failing to disclose negative secondary findings., Conclusion: Trained NGHPs made clinically significant errors in GS result disclosures. Characterizing common errors in result disclosure can illuminate gaps in education to inform the development of future genomics training and alternative service delivery models., Competing Interests: Conflict of Interest All authors declare no competing financial interests in relation to the work described., (Copyright © 2024 American College of Medical Genetics and Genomics. Published by Elsevier Inc. All rights reserved.)

Bi-allelic disruptive variants (nonsense, frameshift, and splicing variants) in KDM5B have been identified as causative for autosomal recessive intellectual developmental disorder type 65. In contrast, dominant variants, usually disruptive as well, have been more difficult to implicate in a specific phenotype, since some of them have been found in unaffected controls or relatives. Here, we describe individuals with likely pathogenic variants in KDM5B , including eight individuals with dominant missense variants. This study is a retrospective case series of 21 individuals with variants in KDM5B . We performed deep phenotyping and collected the clinical information and molecular data of these individuals' family members. We compared the phenotypes according to variant type and to those previously described in the literature. The most common features were developmental delay, impaired intellectual development, behavioral problems, autistic behaviors, sleep disorders, facial dysmorphism, and overgrowth. DD, ASD behaviors, and sleep disorders were more common in individuals with dominant disruptive KDM5B variants, while individuals with dominant missense variants presented more frequently with renal and skin anomalies. This study extends our understanding of the KDM5B -related neurodevelopmental disorder and suggests the pathogenicity of certain dominant KDM5B missense variants.

Costs of implementing genomic testing innovations extend beyond the cost of sequencing, affecting personnel and infrastructure for which little data are available. We developed a time and motion (T&M) study within the Clinical Sequencing Evidence-Generating Research (CSER) consortium to address this gap, and herein describe challenges of conducting T&M studies within a research consortium and the approaches we developed to overcome them. CSER investigators created a subgroup to carry out the T&M study (authors). We describe logistical and administrative challenges associated with resource use data collection across heterogeneous projects conducted in real-world clinical settings, and our solutions for completing this study and harmonizing data across projects. We delineate processes for feasible data collection on workflow, personnel, and resources required to deliver genetic testing innovations in each CSER project. A critical early step involved developing detailed project-specific process flow diagrams of innovation implementation in projects' clinical settings. Analyzing diagrams across sites, we identified common process-step themes, used to organize project-specific data collection and cross-project analysis. Given the heterogeneity of innovations, study design, and workflows, which affect resources required to deliver genetic testing innovations, flexibility was necessary to harmonize data collection. Despite its challenges, this heterogeneity provides rich insights about variation in clinical processes and resource implications for implementing genetic testing innovations., (© 2023 The Authors. Clinical and Translational Science published by Wiley Periodicals LLC on behalf of American Society for Clinical Pharmacology and Therapeutics.)

Purpose: Neurodevelopmental disorders (NDDs) often result from rare genetic variation, but genomic testing yield for NDDs remains below 50%, suggesting that clinically relevant variants may be missed by standard analyses. Here, we analyze "poison exons" (PEs), which are evolutionarily conserved alternative exons often absent from standard gene annotations. Variants that alter PE inclusion can lead to loss of function and may be highly penetrant contributors to disease., Methods: We curated published RNA sequencing data from developing mouse cortex to define 1937 conserved PE regions potentially relevant to NDDs, and we analyzed variants found by genome sequencing in multiple NDD cohorts., Results: Across 2999 probands, we found 6 novel clinically relevant variants in PE regions. Five of these variants are in genes that are part of the sodium voltage-gated channel alpha subunit family (SCN1A, SCN2A, and SCN8A), which is associated with epilepsies. One variant is in SNRPB, associated with cerebrocostomandibular syndrome. These variants have moderate to high computational impact assessments, are absent from population variant databases, and in genes with gene-phenotype associations consistent with each probands reported features., Conclusion: With a very minimal increase in variant analysis burden (average of 0.77 variants per proband), annotation of PEs can improve diagnostic yield for NDDs and likely other congenital conditions., Competing Interests: Conflict of Interest Eimear E. Kenny received personal fees from Illumina, 23andMe, and Regeneron Pharmaceuticals and serves as a scientific advisory board member for Encompass Bio, Foresite Labs, and Galateo Bio. All other authors declare no conflicts of interest., (Copyright © 2023 American College of Medical Genetics and Genomics. Published by Elsevier Inc. All rights reserved.)

Background: It is critical to understand the wide-ranging clinical and non-clinical effects of genome sequencing (GS) for parents in the NICU context. We assessed parents' experiences with GS as a first-line diagnostic tool for infants with suspected genetic conditions in the NICU., Methods: Parents of newborns (N = 62) suspected of having a genetic condition were recruited across five hospitals in the southeast United States as part of the SouthSeq study. Semi-structured interviews (N = 78) were conducted after parents received their child's sequencing result (positive, negative, or variants of unknown significance). Thematic analysis was performed on all interviews., Results: Key themes included that (1) GS in infancy is important for reproductive decision making, preparing for the child's future care, ending the diagnostic odyssey, and sharing results with care providers; (2) the timing of disclosure was acceptable for most parents, although many reported the NICU environment was overwhelming; and (3) parents deny that receiving GS results during infancy exacerbated parent-infant bonding, and reported variable impact on their feelings of guilt., Conclusion: Parents reported that GS during the neonatal period was useful because it provided a "backbone" for their child's care. Parents did not consistently endorse negative impacts like interference with parent-infant bonding.

Purpose: SouthSeq is a translational research study that undertook genome sequencing (GS) for infants with symptoms suggestive of a genetic disorder. Recruitment targeted racial/ethnic minorities and rural, medically underserved areas in the Southeastern United States, which are historically underrepresented in genomic medicine research., Methods: GS and analysis were performed for 367 infants to detect disease-causal variation concurrent with standard of care evaluation and testing., Results: Definitive diagnostic (DD) or likely diagnostic (LD) genetic findings were identified in 30% of infants, and 14% of infants harbored an uncertain result. Only 43% of DD/LD findings were identified via concurrent clinical genetic testing, suggesting that GS testing is better for obtaining early genetic diagnosis. We also identified phenotypes that correlate with the likelihood of receiving a DD/LD finding, such as craniofacial, ophthalmologic, auditory, skin, and hair abnormalities. We did not observe any differences in diagnostic rates between racial/ethnic groups., Conclusion: We describe one of the largest-to-date GS cohorts of ill infants, enriched for African American and rural patients. Our results show the utility of GS because it provides early-in-life detection of clinically relevant genetic variations not detected by current clinical genetic testing, particularly for infants exhibiting certain phenotypic features., Competing Interests: Conflict of Interest All authors declare no competing financial interests in relation to the work described., (Copyright © 2021 American College of Medical Genetics and Genomics. Published by Elsevier Inc. All rights reserved.)

To meet current and expected future demand for genome sequencing in the neonatal intensive care unit (NICU), adjustments to traditional service delivery models are necessary. Effective programs for the training of non-genetics providers (NGPs) may address the known barriers to providing genetic services including limited genetics knowledge and lack of confidence. The SouthSeq project aims to use genome sequencing to make genomic diagnoses in the neonatal period and evaluate a scalable approach to delivering genome sequencing results to populations with limited access to genetics professionals. Thirty-three SouthSeq NGPs participated in a live, interactive training intervention and completed surveys before and after participation. Here, we describe the protocol for the provider training intervention utilized in the SouthSeq study and the associated impact on NGP knowledge and confidence in reviewing, interpreting, and using genome sequencing results. Participation in the live training intervention led to an increased level of confidence in critical skills needed for real-world implementation of genome sequencing. Providers reported a significant increase in confidence level in their ability to review, understand, and use genome sequencing result reports to guide patient care. Reported barriers to implementation of genome sequencing in a NICU setting included test cost, lack of insurance coverage, and turn around time. As implementation of genome sequencing in this setting progresses, effective education of NGPs is critical to provide access to high-quality and timely genomic medicine care.

Background: The desire of parents to obtain a genetic diagnosis for their child with intellectual disability and associated symptoms has long been framed as a diagnostic odyssey, an arduous and sometimes perilous journey focused on the goal of identifying a cause for the child's condition. Methods: Semi-structured interviews (N = 60) were conducted with parents of children (N = 59, aged 2-24 years) with intellectual disability and/or developmental delay (IDD) who underwent genome sequencing at a single pediatric multispecialty clinic. Interviews were conducted after parents received their child's sequencing result (positive findings, negative findings, or variants of unknown significance). Thematic analysis was performed on all interviews. Results: Parents reported that obtaining a genetic diagnosis was one important step in their overall goal of helping their child live their best life possible life. They intended to use the result as a tool to help their child by seeking the correct school placement and obtaining benefits and therapeutic services. Conclusions: For the parents of children with IDD, the search for a genetic diagnosis is best conceptualized as a part of parents' ongoing efforts to leverage various diagnoses to obtain educational and therapeutic services for their children. Cleaving parents' search for a genetic diagnosis from these broader efforts obscures the value that some parents place on a sequencing result in finding and tailoring therapies and services beyond the clinic. Interviews with parents reveal, therefore, that genomic sequencing is best understood as one important stage of an ongoing therapeutic odyssey that largely takes place outside the clinic. Findings suggest the need to expand translational research efforts to contextualize a genetic diagnosis within parents' broader efforts to obtain educational and therapeutic services outside clinical contexts.

The expansion of both formal and informal frameworks of "engaged" research in translational research settings raises emerging and substantial normative concerns. In this article, we draw on findings from a focus group study with members of a national consortium of translational genomic research sites. The goals were to catalog informal participant engagement practices, to explore the perceived roots of these practices and the motivations of research staff members for adopting them, and to reflect on their ethical implications. We learned that participant engagement is a deliberate strategy by research staff members both to achieve instrumental research goals and to "do research differently" in response to past research injustices. While many of the participant engagement practices used in translational genomic research are not new, important insights can be gained through a closer examination of the specific contours of participant engagement in this context. These practices appear to have been shaped by the professional training of genetic counselors and by the interests and needs of participants who enroll in clinical genomics studies. The contours of this contemporary application of engaged research principles have relevance not only to clinical genomics research but also to translational research broadly, particularly for how communities of clinical researchers are interpreting the principle of respect for persons. Our findings invite normative questions about the governance of these practices and sociological questions about whether and how clinical researchers in other professions are also engaging participants in translational research settings., (© 2019 by The Hastings Center. All rights reserved.)

We identified individuals with variations in ACTL6B, a component of the chromatin remodeling machinery including the BAF complex. Ten individuals harbored bi-allelic mutations and presented with global developmental delay, epileptic encephalopathy, and spasticity, and ten individuals with de novo heterozygous mutations displayed intellectual disability, ambulation deficits, severe language impairment, hypotonia, Rett-like stereotypies, and minor facial dysmorphisms (wide mouth, diastema, bulbous nose). Nine of these ten unrelated individuals had the identical de novo c.1027G>A (p.Gly343Arg) mutation. Human-derived neurons were generated that recaptured ACTL6B expression patterns in development from progenitor cell to post-mitotic neuron, validating the use of this model. Engineered knock-out of ACTL6B in wild-type human neurons resulted in profound deficits in dendrite development, a result recapitulated in two individuals with different bi-allelic mutations, and reversed on clonal genetic repair or exogenous expression of ACTL6B. Whole-transcriptome analyses and whole-genomic profiling of the BAF complex in wild-type and bi-allelic mutant ACTL6B neural progenitor cells and neurons revealed increased genomic binding of the BAF complex in ACTL6B mutants, with corresponding transcriptional changes in several genes including TPPP and FSCN1, suggesting that altered regulation of some cytoskeletal genes contribute to altered dendrite development. Assessment of bi-alleic and heterozygous ACTL6B mutations on an ACTL6B knock-out human background demonstrated that bi-allelic mutations mimic engineered deletion deficits while heterozygous mutations do not, suggesting that the former are loss of function and the latter are gain of function. These results reveal a role for ACTL6B in neurodevelopment and implicate another component of chromatin remodeling machinery in brain disease., (Copyright © 2019 American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.)

Purpose: Clinical sequencing emerging in health care may result in secondary findings (SFs)., Methods: Seventy-four of 6240 (1.2%) participants who underwent genome or exome sequencing through the Clinical Sequencing Exploratory Research (CSER) Consortium received one or more SFs from the original American College of Medical Genetics and Genomics (ACMG) recommended 56 gene-condition pair list; we assessed clinical and psychosocial actions., Results: The overall adjusted prevalence of SFs in the ACMG 56 genes across the CSER consortium was 1.7%. Initially 32% of the family histories were positive, and post disclosure, this increased to 48%. The average cost of follow-up medical actions per finding up to a 1-year period was $128 (observed, range: $0-$678) and $421 (recommended, range: $141-$1114). Case reports revealed variability in the frequency of and follow-up on medical recommendations patients received associated with each SF gene-condition pair. Participants did not report adverse psychosocial impact associated with receiving SFs; this was corroborated by 18 participant (or parent) interviews. All interviewed participants shared findings with relatives and reported that relatives did not pursue additional testing or care., Conclusion: Our results suggest that disclosure of SFs shows little to no adverse impact on participants and adds only modestly to near-term health-care costs; additional studies are needed to confirm these findings.

CYFIP2, encoding the evolutionary highly conserved cytoplasmic FMRP interacting protein 2, has previously been proposed as a candidate gene for intellectual disability and autism because of its important role linking FMRP-dependent transcription regulation and actin polymerization via the WAVE regulatory complex (WRC). Recently, de novo variants affecting the amino acid p.Arg87 of CYFIP2 were reported in four individuals with epileptic encephalopathy. We here report 12 independent patients harboring a variety of de novo variants in CYFIP2 broadening the molecular and clinical spectrum of a novel CYFIP2-related neurodevelopmental disorder. Using trio whole-exome or -genome sequencing, we identified 12 independent patients carrying a total of eight distinct de novo variants in CYFIP2 with a shared phenotype of intellectual disability, seizures, and muscular hypotonia. We detected seven different missense variants, of which two occurred recurrently (p.(Arg87Cys) and p.(Ile664Met)), and a splice donor variant in the last intron for which we showed exon skipping in the transcript. The latter is expected to escape nonsense-mediated mRNA decay resulting in a truncated protein. Despite the large spacing in the primary structure, the variants spatially cluster in the tertiary structure and are all predicted to weaken the interaction with WAVE1 or NCKAP1 of the actin polymerization regulating WRC-complex. Preliminary genotype-phenotype correlation indicates a profound phenotype in p.Arg87 substitutions and a more variable phenotype in other alterations. This study evidenced a variety of de novo variants in CYFIP2 as a novel cause of mostly severe intellectual disability with seizures and muscular hypotonia.

Purpose: Clinically relevant secondary variants were identified in parents enrolled with a child with developmental delay and intellectual disability., Methods: Exome/genome sequencing and analysis of 789 "unaffected" parents was performed., Results: Pathogenic/likely pathogenic variants were identified in 21 genes within 25 individuals (3.2%), with 11 (1.4%) participants harboring variation in a gene defined as clinically actionable by the American College of Medical Genetics and Genomics. These 25 individuals self-reported either relevant clinical diagnoses (5); relevant family history or symptoms (13); or no relevant family history, symptoms, or clinical diagnoses (7). A limited carrier screen was performed yielding 15 variants in 48 (6.1%) parents. Parents were also analyzed as mate pairs (n = 365) to identify cases in which both parents were carriers for the same recessive disease, yielding three such cases (0.8%), two of which had children with the relevant recessive disease. Four participants had two findings (one carrier and one noncarrier variant). In total, 71 of the 789 enrolled parents (9.0%) received secondary findings., Conclusion: We provide an overview of the rates and types of clinically relevant secondary findings, which may be useful in the design and implementation of research and clinical sequencing efforts to identify such findings.

As genomic sequencing expands, so does our knowledge of the link between genetic variation and disease. Deeper catalogs of variant frequencies improve identification of benign variants, while sequencing affected individuals reveals disease-associated variation. Accumulation of human genetic data thus makes reanalysis a means to maximize the benefits of clinical sequencing. We implemented pipelines to systematically reassess sequencing data from 494 individuals with developmental disability. Reanalysis yielded pathogenic or likely pathogenic (P/LP) variants that were not initially reported in 23 individuals, 6 described here, comprising a 16% increase in P/LP yield. We also downgraded 3 LP and 6 variants of uncertain significance (VUS) due to updated population frequency data. The likelihood of identifying a new P/LP variant increased over time, as ~22% of individuals who did not receive a P/LP variant at their original analysis subsequently did after 3 years. We show here that reanalysis and data sharing increase the diagnostic yield and accuracy of clinical sequencing., (© 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

N-alpha-acetylation is a common co-translational protein modification that is essential for normal cell function in humans. We previously identified the genetic basis of an X-linked infantile lethal Mendelian disorder involving a c.109T>C (p.Ser37Pro) missense variant in NAA10, which encodes the catalytic subunit of the N-terminal acetyltransferase A (NatA) complex. The auxiliary subunit of the NatA complex, NAA15, is the dimeric binding partner for NAA10. Through a genotype-first approach with whole-exome or genome sequencing (WES/WGS) and targeted sequencing analysis, we identified and phenotypically characterized 38 individuals from 33 unrelated families with 25 different de novo or inherited, dominantly acting likely gene disrupting (LGD) variants in NAA15. Clinical features of affected individuals with LGD variants in NAA15 include variable levels of intellectual disability, delayed speech and motor milestones, and autism spectrum disorder. Additionally, mild craniofacial dysmorphology, congenital cardiac anomalies, and seizures are present in some subjects. RNA analysis in cell lines from two individuals showed degradation of the transcripts with LGD variants, probably as a result of nonsense-mediated decay. Functional assays in yeast confirmed a deleterious effect for two of the LGD variants in NAA15. Further supporting a mechanism of haploinsufficiency, individuals with copy-number variant (CNV) deletions involving NAA15 and surrounding genes can present with mild intellectual disability, mild dysmorphic features, motor delays, and decreased growth. We propose that defects in NatA-mediated N-terminal acetylation (NTA) lead to variable levels of neurodevelopmental disorders in humans, supporting the importance of the NatA complex in normal human development., (Copyright © 2018 American Society of Human Genetics. All rights reserved.)

Background: Developmental disabilities have diverse genetic causes that must be identified to facilitate precise diagnoses. We describe genomic data from 371 affected individuals, 309 of which were sequenced as proband-parent trios., Methods: Whole-exome sequences (WES) were generated for 365 individuals (127 affected) and whole-genome sequences (WGS) were generated for 612 individuals (244 affected)., Results: Pathogenic or likely pathogenic variants were found in 100 individuals (27%), with variants of uncertain significance in an additional 42 (11.3%). We found that a family history of neurological disease, especially the presence of an affected first-degree relative, reduces the pathogenic/likely pathogenic variant identification rate, reflecting both the disease relevance and ease of interpretation of de novo variants. We also found that improvements to genetic knowledge facilitated interpretation changes in many cases. Through systematic reanalyses, we have thus far reclassified 15 variants, with 11.3% of families who initially were found to harbor a VUS and 4.7% of families with a negative result eventually found to harbor a pathogenic or likely pathogenic variant. To further such progress, the data described here are being shared through ClinVar, GeneMatcher, and dbGaP., Conclusions: Our data strongly support the value of large-scale sequencing, especially WGS within proband-parent trios, as both an effective first-choice diagnostic tool and means to advance clinical and research progress related to pediatric neurological disease.