Genotype and Phenotype of Caffeine Metabolism in Identical Twins

Abstract

A wide range of individual variability to caffeine's effects have been reported in the literature, with factors including gene variants, gender, and personal habits modulating the response to caffeine. For example, the literature suggests that a single nucleotide polymorphism (SNP) in intron 1 of the CYP1A2 gene is associated with “fast” versus “slow” caffeine metabolism. The goal of our study was to genotype and phenotype identical twins to investigate environmental versus genetic influences on caffeine metabolism. For genotyping, we are using PCR‐RFLP to determine C/A at rs762551. For phenotyping, we are using a micro‐scale solid phase extraction of caffeine from saliva, determining the concentration of caffeine via GC‐MS, and using the loss of caffeine over time to monitor the activity of CYP1A2, the principal enzyme for caffeine metabolism. Initial results suggest a good correlation of caffeine half‐lives within identical twin pairs. However, it was not possible to predict this half‐life based on rs762551 genotype. Our findings indicate a strong influence of behavioral factors such as daily caffeine consumption on CYP1A2 activity. These findings could have significance for optimizing the ergogenic effects of caffeine dosing.Support or Funding InformationInstitutional Development Award (IDeA) from the National Institute of General Medical Sciences of the National Institutes of Health under grant number P20GM0103423This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.