Identification, classification, and genomic annotation of sex-specific eQTLs. (A) Our analysis revealed 2408 sex-specific eQTLs (P < 1 × 10−4). We classified the sex-specific eQTLs into the following groups: sex-specific effect, sex-specific direction, and sex-specific magnitude. (B) Here we show distributions of heritability and eQTL effect size, with data for females and males colored in red and blue, respectively (the horizontal axes indicate counts for females on the left half and males on the right half). We found that heritability was elevated for females (P < 2.2 × 10−16, Mann–Whitney U test) and that the sex-specific eQTL effect sizes (i.e., regression coefficients) were also elevated for females (P < 2.2 × 10−16, Mann–Whitney U test). (C) Quantification of the sex-specific eQTL groups yielded the following relative contributions: 33% sex-specific effect, 66% sex-specific magnitude, and 1% sex-specific direction eQTLs. (D) We used ChromHMM data to document the genomic context of the sex-specific eQTLs in pre-adipocytes and adipocytes. Approximately 30% of the eQTL SNPs were within transcription start sites, enhancers, or transcribed regions.
