Genetics in Medicine最新文献

Purpose: Pathogenic germline variants (PGVs) in a subset of cancer predisposition genes (CPGs) are associated with adult-onset autosomal dominant (AD) cancer susceptibility and life-limiting autosomal recessive (AR) disease. Counseling in adult cancer genetics clinics regarding reproductive risk for PGV heterozygotes is limited.

Methods: Estimated heterozygote frequencies across ancestries were calculated for AD CPGs with AR risk (ATM, BRCA1, BRCA2, BRIP1, FH, NBN, MLH1, MSH2, MSH6, PMS2, RAD51C, SDHA, SDHB, and SDHD) from gnomADv.3.0, the Penn Medicine Biobank, and FLOSSIES.

Results: Average frequencies of heterozygotes with PGVs across ancestries for BRCA1 and BRCA2 were 0.33% ± 0.41% and 0.43% ± 0.36%, with variability cross-ancestry from 0.06% to 1.32% and 0.17% to 1.29%, respectively. ATM had the next highest PGV heterozygote frequency (0.31% ± 0.12%) and SDHD the lowest (0.01% ± 0.01%) average PGV heterozygote frequency. Heterozygote PGV frequencies from gnomAD were similar as cancer-free individuals in Penn Medicine Biobank and higher than in the FLOSSIES data.

Discussion: Heterozygote frequency estimates for AD CPGs that cause AR disease provides information to facilitate discussions regarding reproductive risk. Future studies are needed to assess whether utilization of these data will influence couples' reproductive risk planning.

The Clinical Genome Resource (ClinGen) is a National Institutes of Health-funded program founded 10 years ago that defines the clinical relevance of genes and variants for medical and research use. ClinGen working groups develop standards for data sharing and curating genomic knowledge. Expert panels, with >2500 active members from 67 countries, curate the validity of monogenic disease relationships, pathogenicity of genetic variation, dosage sensitivity of genes, and actionability of gene-disease interventions using ClinGen standards, infrastructure, and curation interfaces. Results are available on clinicalgenome.org and classified variants are also submitted to ClinVar, a publicly available database hosted by the National Institutes of Health. As of January 2024, over 2700 genes have been curated (2420 gene-disease relationships for validity, 1557 genes for dosage sensitivity, and 447 gene-condition pairs for actionability), and 5161 unique variants have been classified for pathogenicity. New efforts are underway in somatic cancer, complex disease and pharmacogenomics, and a systematic approach to addressing justice, equity, diversity, and inclusion. ClinGen's knowledge can be used to build evidence-based genetic testing panels, interpret copy-number variation, resolve discrepancies in variant classification, guide disclosure of genomic findings to patients, and assess new predictive algorithms. To get involved in ClinGen activities go to https://www.clinicalgenome.org/start.

Purpose: To characterize the diagnostic and clinical outcomes of a cohort of critically ill infants and children with suspected mitochondrial disorders (MD) undergoing ultra-rapid genomic testing as part of a national program.

Methods: Ultra-rapid genomic sequencing was performed in 454 families (genome sequencing: n=290, exome sequencing +/- mitochondrial DNA sequencing: n=164). In 91 individuals, MD was considered, prompting analysis using an MD virtual gene panel. These individuals were reviewed retrospectively and scored according to modified Nijmegen Mitochondrial Disease Criteria.

Results: A diagnosis was achieved in 47% (43/91) of individuals, 40% (17/43) of whom had an MD. Seven additional individuals in whom an MD was not suspected were diagnosed with an MD following broader analysis. Gene-agnostic analysis led to the discovery of two novel disease genes, with pathogenicity validated through targeted functional studies (CRLS1 and MRPL39). Functional studies enabled diagnosis in another four individuals. Of the 24 individuals ultimately diagnosed with an MD, 79% had a change in management, which included 53% whose care was redirected to palliation.

Conclusion: Ultra-rapid genetic diagnosis of MD in acutely unwell infants and children is critical for guiding decisions about the need for additional investigations and clinical management.

Purpose: This study aimed to identify phenotypic factors associated with genetic diagnoses in patients with neurodevelopmental disorders and generate a decision tree to assist clinicians in identifying patients most likely to receive a positive result on genetic testing.

Methods: We retrospectively reviewed the charts of 316 patients evaluated in a neurodevelopmental clinic between 2014 and 2019. Patients were categorized based on genetic test results. Analyses were performed to identify variables that discriminate between patients with and without a genetic diagnosis.

Results: Patients with a genetic diagnosis were more likely to be female and have a history of motor delay, hypotonia, congenital heart disease, and early intervention. Classification and regression tree analysis revealed that 75% of patients with motor delay had a genetic diagnosis. In patients without motor delay, hypotonia, age of walking, and age at initial evaluation were important indicators of a genetic diagnosis.

Conclusion: Our findings suggest that motor delay and hypotonia are associated with genetic diagnoses in children with neurodevelopmental disorders. The decision tree highlights patient subsets at greater risk and suggests possible phenotypic screens. Future studies could develop validated decision trees based on phenotypic data to assist clinicians in stratifying patients for genetic testing.