ABSTRACT
Motivation: The proliferation of genetic testing and consumer genomics represents a logistic challenge to the personalized use of GWAS data in VCF format. Specifically, the challenge of retrieving target genetic variation from large compressed files filled with unrelated variation information. Compounding the data traversal challenge, privacy-sensitive VCF files are typically managed as large stand-alone single files (no companion index file) composed of variable-sized compressed chunks, hosted in consumer-facing environments with no native support for hosted execution. Results: A portable JavaScript module was developed to support in-browser fetching of partial content using byte-range requests. This includes on-the-fly decompressing irregularly positioned compressed chunks, coupled with a binary search algorithm iteratively identifying chromosome-position ranges. The in-browser zero-footprint solution (no downloads, no installations) enables the interoperability, reusability, and user-facing governance advanced by the FAIR principles for stewardship of scientific data. Availability - https://episphere.github.io/vcf, including supplementary material.
ABSTRACT
OBJECTIVE: To investigate whether a child's genotype affects a mother's risk of rheumatoid arthritis (RA) beyond the risk associated with her genotype and to test whether exposure to fetal alleles inherited from the father increases risk of RA among mothers without risk alleles. METHODS: A case-control study was conducted among 1165 mothers (170 cases/995 controls) and their respective 1482 children. We tested the association between having any child with alleles encoding amino acids (AAs) associated with RA including the 'shared epitope' (SE) and DERAA AA sequences at positions 70-74; AA valine, lysine and alanine at positions 11, 71 and 74 of HLA-DRB1; aspartic acid at position 9 of HLA-B and phenylalanine at position 9 of DPB1. We used logistic regression models to estimate OR and 95% CI for each group of alleles, adjusting for maternal genotype and number of live births. RESULTS: We found increased risk of RA among mothers who had any child with SE (OR 3.0; 95% CI 2.0 to 4.6); DERAA (OR 1.7; 95% CI 1.1 to 2.6); or valine (OR 2.3; 95% CI 1.6 to 3.5), lysine (OR 2.3; 95% CI 1.5 to 3.4) and alanine (OR 2.8; 95% CI 1.2 to 6.4) at DRB1 positions 11, 71 and 74, respectively. Among non-carrier mothers, increased risk of RA was associated with having children who carried DERAA (OR 1.7; 95% CI 1.0 to 2.7) and alleles encoding lysine at DRB1 position 71 (OR 2.3; 95% CI 1.5 to 4.8). CONCLUSION: Findings support the hypothesis that a child's genotype can contribute independently to risk of RA among mothers.
