Genetics in Medicine最新文献

Measurement of lysosomal disease (LD) biomarkers can reveal valuable information about disease status. Lyso-globotriaosylceramide (lyso-Gb₃), glucosylsphingosine (lyso-Gb₁), galactosylsphingosine (psychosine), and glucose tetrasaccharide (Glca1-6Glca1-4Glca1-4Glc, Glc₄) are biomarkers associated with Fabry, Gaucher, Krabbe, and Pompe disease, respectively. Clinical biomarker testing is performed to guide patient management, including monitoring disease progression and initiating treatment, and in diagnostic evaluations of either symptomatic patients or asymptomatic individuals with a positive family history or abnormal newborn screen. Biomarker analysis can be performed through independent analysis of a single analyte or as a multiplex assay measuring analytes for more than one disorder utilizing liquid chromatographic separation and tandem mass spectrometric detection. These guidelines were developed to provide technical standards for biomarker analysis, results interpretation, and results reporting, highlighting Fabry, Gaucher, Krabbe, and Pompe diseases as examples.

Purpose: This study sought to better understand primary care providers' (PCPs) readiness to conduct population-based risk assessment and offer genetic testing for hereditary cancer.

Methods: Sixty PCPs completed a survey assessing their current practices, attitudes, and confidence with cancer risk assessment and testing. Sixteen participated in follow-up interviews. Descriptive statistics are presented and supported by qualitative data.

Results: Providers preferred direct questioning over standardized screening tools. In interviews, providers said they are not ordering cancer-risk genetic testing even when it might be appropriate. Ninety-eight percent agree testing is important to clinical care, but 73% agree that it could negatively impact patients. Ninety percent were willing to offer targeted testing, but only 68% were willing to offer population-based risk assessment. Confidence performing different behaviors necessary in a cancer risk assessment varied, with only 32% confident responding to questions specifically related to genetic testing.

Conclusion: Providers are willing to offer genetic testing, but unlikely to do so because they lack confidence in genetics-specific skill areas. Unsystematic approaches to family history screening and fears about follow up complexity may exacerbate health disparities. Interventions to increase provider confidence in ascertaining and managing hereditary cancer are needed to achieve widespread adoption of population-based risk assessment and guideline-recommended genetic testing.

Purpose: Better understanding patient uptake of pharmacogenomic (PGx) testing may inform its implementation and maximize the benefits that such testing can confer. This study examined patient and provider factors associated with PGx test ordering in a national healthcare system where panel-based testing was implemented as part of routine care.

Methods: We used a retrospective matched cohort design and data from the Veterans Health Administration Corporate Data Warehouse. A conditional logistic model was used to identify factors associated with a PGx order receipt and estimate odds ratios and 95% confidence intervals.

Results: The following patient factors predicted receipt of a PGx test order: younger age, married status, rural residence, non-Hispanic Black or Hispanic race/ethnicity, PGx educational mailer receipt, depression diagnosis, allergy to a drug on the panel, prescriptions for drugs on the panel, and specialty care visits (p<0.05). Additionally, patients whose providers were female, younger, a nurse practitioner/physician assistant or pharmacist, or participated in an educational mailer program were more likely to receive an order (p<0.05).

Conclusion: This study highlights factors that may facilitate or hinder the widespread and equitable implementation of PGx testing in a large national healthcare system. The information is being used to further refine the program.

Purpose: Monogenic rare diseases contribute significantly to infant deaths and pediatric hospitalizations and cause burden to the patients and their families. The American College of Medical Genetics and Genomics recommended in 2021 that carrier screening of autosomal recessive and X-linked conditions with a carrier frequency of ≥ 1/200 and a severe or moderate phenotype should be offered when planning or during pregnancy. In November 2023 gnomAD v4.0 was released. It contains in total 807,162 individuals, being nearly 5x larger than previous versions, that have been used to estimate gene carrier frequencies (GCF).

Methods: We utilized gnomAD v4.0 (GRCh38) to calculate the GCFs for available genetic ancestry groups for variants having pathogenic or likely pathogenic classification (>80% of submissions) in ClinVar. We calculated GCF separately for exomes and genomes, and combined data, and at-risk couple frequencies (ACF) per genetic ancestry group RESULTS: In total, 324 genes had a GCF ≥ 1/200 in at least one ancestry subgroup. The number of genes with GCF ≥ 1/200 varied greatly between subgroups. ACFs were more similar, Ashkenazi Jewish having the highest ACF of 6.11%.

Conclusion: Improved understanding of carrier risks and updated carrier screening content would allow patients to make more informed reproductive decisions.

Objective: To develop and assess the face and construct validity of the Clinician-reported Genetic testing Utility InDEX (C-GUIDE^TM) for genetic testing in prenatal care.

Methods: Following a literature review and consultation with clinical experts, a preliminary draft of C-GUIDE Prenatal was developed. Its face and content validity were then assessed by 19 prenatal genetics' providers using interviews and surveys. Feedback informed further revisions. To test construct validity, four geneticist raters completed C-GUIDE on a retrospective sample of cases that received prenatal genetic testing and completed a concurrent global assessment of utility of these cases using an anchor item. A generalized estimating equations model was used to adjust for rater correlation and measure the association between C-GUIDE scores, global item scores, and potential clinical variables.

Results: To develop C-GUIDE Prenatal, 7 items were removed, 10 items were modified, and 4 items were added. For 101 cases rated for validation, on average, a 1-point increase in the global item score was associated with an increase of 1.1 in the C-GUIDE score (p=0.04). Compared to uninformative results, informative positive and informative negative results were associated with a mean increase of 10.7 (SE=1.05) (p<0.001) and 5.6 (SE=1.85) (p<0.001), respectively. As indications for testing, known/familial variants were associated with a mean increase in the C-GUIDE score of 4.7 (SE=2.21) (p < 0.001) compared to ultrasound findings. C-GUIDE scores increased by a mean of 3.0 (SE=0.23) among cases for whom pregnancies were ongoing compared to those for whom they were not (p<0.01).

Conclusions: The significant positive associations between C-GUIDE total and the global item score and between C-GUIDE total, result type, indication for testing, and pregnancy status in the expected directions provide evidence of construct validity.

Purpose: Current practice is to report and manage likely pathogenic/pathogenic variants in a given cancer susceptibility gene (CSG) as though having equivalent penetrance, despite increasing evidence of inter-variant variability in risk associations. Using existing variant interpretation approaches, largely based on full-penetrance models, variants where reduced penetrance is suspected may be classified inconsistently and/or as variants of uncertain significance (VUS). We aimed to develop a national consensus approach for such variants within the Cancer Variant Interpretation Group UK (CanVIG-UK) multidisciplinary network.

Methods: A series of surveys and live polls were conducted during and between CanVIG-UK monthly meetings on various scenarios potentially indicating reduced penetrance. These informed the iterative development of a framework for the classification of variants of reduced penetrance by the CanVIG-UK Steering and Advisory Group (CStAG) working group.

Results: CanVIG-UK recommendations for amendment of the 2015 ACMG/AMP variant interpretation framework were developed for variants where (A) Active evidence suggests a reduced penetrance effect size (e.g. from case-control or segregation data) (B) Reduced penetrance effect is inferred from weaker/potentially-inconsistent observed data.

Conclusions: CanVIG-UK propose a framework for the classification of variants of reduced penetrance in high-penetrance genes. These principles, whilst developed for CSGs, are potentially applicable to other clinical contexts.

Purpose: Maple syrup urine disease (MSUD) is a rare inherited metabolic disease characterised by recurrent metabolic decompensations, neurocognitive impairment, and limited life expectancy. This meta-analysis aims to evaluate the impact of early diagnosis by newborn screening (NBS) on mortality and neurocognitive outcome in survivors, taking into account the quality of national healthcare systems.

Methods: Systematic literature search was performed according to PRISMA-P. Effects on outcome parameters were analysed using meta-analytical measures and re-analysis of individual participant data.

Results: Thirty-three studies were included, reporting on 1141 individuals with MSUD. Participants with classic MSUD presented a more severe phenotype compared to variant MSUD as demonstrated by higher mortality rate (17.1% versus 0%), and lower median IQ (90 versus 104; P<.001, linear mixed model). NBS was associated with improved cognition (mean IQ: 95 versus 82; P=.014, random effects model), and decreased mortality (3% versus 14.6%; P=.028, Kaplan-Meier estimates) compared to individuals identified after onset of symptoms, in trend even after exclusion of individuals with variant MSUD. Quality of national healthcare systems correlated with survival (P=.025, meta-regression) and permanent neurological symptoms (P=.031, meta-regression).

Conclusion: NBS is a prerequisite to improved outcome in individuals with MSUD; however, health benefit critically depends on the quality of the national healthcare systems.

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.