More than 90% of Americans consume caffeine daily, but the amount consumed varies widely. Previous studies have shown that genes related to caffeine metabolism and receptor binding may influence caffeine consumption. A better understanding of the relationship between genotype and caffeine consumption has the potential to inform mechanisms of this common dietary behavior.

We performed a genome-wide association study (GWAS) of self-reported consumption data combining a wide range of caffeinated beverages including coffee, tea, soda, and energy drinks in the Coriell Personalized Medicine Collaborative (N=2,830) using a generalized linear model. Our analysis identified several candidate loci implicated in caffeine consumption. One previously identified SNP associated with caffeine consumption and replicated in the current study, rs2472297 (P-value=3.8x10-6), is located in an intergenic region between CYP1A1 and CYP1A2 (the gene that encodes the enzyme primarily responsible for caffeine metabolism), and has been associated with caffeine consumption in prior studies. Our results further support follow-up functional studies focused on the role of CYP1A1 and CYP1A2 on caffeine consumption habits, metabolism, and health status and outcomes.