PT - JOURNAL ARTICLE AU - Brandon L. Pierce AU - Lin Tong AU - Maria Argos AU - Farzana Jasmine AU - Muhammad Rakibuz-Zaman AU - Golam Sarwar AU - Md. Tariqul Islam AU - Hasan Shahriar AU - Tariqul Islam AU - Mahfuzar Rahman AU - Md. Yunus AU - Muhammad G. Kibriya AU - Lin S. Chen AU - Habibul Ahsan TI - Co-occurring eQTLs and mQTLs: detecting shared causal variants and shared biological mechanisms AID - 10.1101/094656 DP - 2016 Jan 01 TA - bioRxiv PG - 094656 4099 - http://biorxiv.org/content/early/2016/12/15/094656.short 4100 - http://biorxiv.org/content/early/2016/12/15/094656.full AB - Inherited genetic variation impacts local gene expression and DNA methylation in humans. Expression and methylation quantitative trait loci (cis-eQTLs and cis-mQTLs) often occur at the same genomic location, suggesting a common causal variant and shared mechanism. Using DNA and RNA from peripheral blood of Bangladeshi individuals, we use “co-localization” methods to identify 3,695 eQTL-mQTL pairs that are likely to share a causal variant. Using partial correlation analysis and mediation analysis, we identify >500 pairs with evidence of a causal relationships between expression and methylation (i.e., shared mechanism) with many additional pairs that we are underpowered to detect. These co-localized pairs are enriched for SNPs showing opposite effects on expression and methylation, although a many affect multiple CpGs in opposite directions. Evidence of shared SNP-age interaction also supports shared mechanisms for two eQTL-mQTL pairs. This work demonstrates the pervasiveness of co-regulated expression and methylation traits in the human genome. This approach can be applied to other types of molecular QTLs to enhance our understanding of regulatory mechanisms.