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Heritable bacteria

How can researchers figure out the role of your genetics in determining the kinds of bacteria you have in your gut? Get over a thousand sets of twins and do some fancy testing. We describe the results here.

Study under review: Genetic determinants of the gut microbiome in UK twins

Introduction

It is generally accepted that many environmental and lifestyle factors influence the composition of the gut microbiome, including age, diet, and disease state. Less well-investigated is the role that host genetics play in shaping microbiome composition.

Although preliminary evidence[1] in humans and mice have suggested that specific strains of bacteria in the gut are associated with host genetic variation, other research has contested these findings. Specifically, research comparing[2] the similarity[3] of the microbiome in monozygotic twins to dizygotic twins found no significant differences, which suggests that genetics and heritability do not play a role in determining microbiome composition. However, these studies used small sample sizes (about 20-60 twin pairs total) that may have reduced the ability to detect a statistically significant difference between the groups.

Who and what was studied?

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What were the findings?

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What does the study really tell us?

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The big picture

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Frequently Asked Questions

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What should I know?

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