Nutri(meta)genetics and cardiovascular disease: novel concepts in the interaction of diet and genomic variation.

In addition to the interaction of nutrition and genetic variation on the genesis and natural history of cardiovascular disease, recent studies have revealed an entire new genome that resides in the trillions of microbes that exist in various human habitats, predominantly in the gut, that may also contribute to the pathogenesis of cardiovascular disease. This microbial genome and the proteins for which it codes have important functions in homeostatic adaptations to the past and present changes in diet and environment accompanying human civilization. Both preclinical and clinical investigations suggest the role of commensal microbiota in promoting adverse cardiovascular risk. Specifically, microbial metabolism of methylated amines leads to direct pro-atherogenic effects in humans. Further investigations are needed to understand the complex relationships among nutritional status, genetic variation, and the microbial genome, which may explain the recent negative results of clinical trials of nutritional interventions such as B vitamin therapy to lower plasma homocysteine levels. The results of such contemporary genomic investigations would allow us to utilize personalized nutritional interventions to reduce cardiovascular risk.