There’s no denying that caffeine fuels epigenetic discovery, but now a recent epigenome-wide association study (EWAS) offers up a different epigenetic perspective about your daily caffeine fix.
This creative rush comes at you from a European collaboration led by Uppsala University (Sweden). The team brewed up the first epigenome-wide association study (EWAS) of coffee and tea consumption by examining four European cohorts (N=3,096) with the 450K array to survey DNA methylation in whole blood. Since the men and women showed different preferences for tea and coffee consumption, they performed both combined and sex separated meta-analyses. Here’s what the tea leaves read:
- After multiple testing correction and adjusting for inflation, the female specific analysis revealed two significant individual CpG sites belonging to DNAJC16 and TTC17
- Interestingly, there are no significant CpGs in the sex combined analysis or the male-specific analyses
- The team then adjusted their ‘zoom’ and switched over to a larger-scale analysis of differentially methylated regions (DMRs), which identified 28 DMRs belonging to 17 different genes on 13 different chromosomes
- Just like the individual CpG site analysis, there were no significant DMRs in the sex combined or male specific analyses
Interestingly, many of the identified genes are associated with cancer risk and/or interact with estrogen. First author Weronica Ek shares, “Previous studies have shown that tea consumption reduces estrogen levels, which highlights a potential difference between the biological response to tea in men and women. Women also drink higher amounts of tea compared to men, which increases our power to find association in women.” Adding to the potential mechanism is fact that tea polyphenols inhibit DNA methyltransferases. While the meta-analysis provides new insight into our environmentally responsive epigenomes, it also leaves us and the authors wondering about which variety of tea is the key to oolong life.
Get the rest of your caffeine fix over at Human Molecular Genetics, May 2017