Twin study reveals how genetics influences the gut microbiome

Personalised probiotic therapies could become a key component in preventing obesity related disease

A fascinating study published in the journal Cell describes how genetics shapes the microbiome of the human gastrointestinal system, which can ultimately influence weight.

This research increases our understanding of how manipulating the types of microbes that live in the human body may have future implications for the treatment of obesity related disorders.

Previous research has assumed the relationship between human genetic variation and the diversity of gut microbes to be minimal. The Cell study, funded by the US National Institutes of Health, shifts that view. To explore this relationship, researchers examined the genes of microbes found in more than 1000 faecal samples from 416 pairs of twins.

They found that specific types of microbes were in greater abundance more often in identical twins, who share 100% of their genes, than in non-identical twins, who share about half of their genes. Such a finding demonstrates the degree to which the host genome influences the composition of gut microbes.

This study, by shedding light on the genetic component of the gut microbiome, also illuminated the significance of another recent breakthrough in the field of bacteriology — the identification of Christensenellaceae, the family of bacteria whose abundance is most heavily influenced by host genetics.

Christensenellaceae are more abundant in hosts with low body weight than in obese people. In fact, mice treated with this microbe gained less weight than untreated mice, suggesting that an increase in the amount of this microbe may help prevent or reduce obesity. Although all research is published with a caveat that it is preliminary, findings like these, if explored further, may actually presage a future in which personalised probiotic therapies become a key component to stopping the epidemic of obesity related disease.