Genome wide association study of vaginal microbiota genetic diversity in French women

TL;DR

This study explores how human genetic variations might influence the diversity of the vaginal microbiota in French women.

Contribution

This is one of the first genome-wide association studies (GWAS) to use microbial genetic data instead of symptoms to analyze vaginal microbiota.

Findings

Shannon diversity of the vaginal microbiota is the trait most strongly explained by human genetic factors.

Two genomic regions were identified as being associated with variations in microbiota diversity.

The study suggests the need for larger and more comprehensive studies to confirm these findings.

Abstract

The composition of the vaginal microbiota is known to be highly structured into five main community state types (CSTs) that are found in all human populations. Several associations between self-reported ethnicity and the type of community have been reported.

Analysing data from in 168 women from the PAPCLEAR cohort study in France, we perform a genome wide association studies (GWAS) looking for human genetic polymorphisms that may impact vaginal microbiota community composition.

We show that Shannon diversity is the trait related to the vaginal microbiota that is best explained by the human genome. Furthermore, we identify two genomic regions associated with its variations.

This is one of the first GWAS to use microbial genetic data instead of symptoms to characterise the vaginal microbiota and our results call for more powered studies in terms of participants and genome coverage.

In all the populations sampled across the world, the composition of the vaginal microbiota falls into five main community state types (CST), four of which are dominated by a single species of Lactobacillus bacteria. Furthermore, the relative frequency of these CSTs consistently varies according to covariates related to age or lifestyle. In particular, several studies report that CST frequency vary with self-reported ethnicity. However, to date, very few genome wide association studies (GWAS) have been performed on the diversity of the vaginal microbiota to identify genetic variants that could explain the observed variation.

Building on the PAPCLEAR cohort, which was set up in Montpellier (France) to study HPV infections and the vaginal microbiota, we perform a GWAS using the Shannon diversity of the vaginal microbiota as our response trait. We identify two genomic regions associated with microbiota diversity variations.

This is one of the first GWAS to use microbial genetic data instead of symptoms to characterise the vaginal microbiota and our results call for more powered studies in terms of participants and genome coverage.

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