Secretor Status Is Strongly Associated with Microbial Alterations Observed during Pregnancy

<div><p>During pregnancy there are significant changes in gut microbiota composition and activity. The impact of secretor status as determined by genotyping <i>FUT2</i> (fucosyltransferase 2) gene was taken as one of the confounding factors associated with faecal microbiota changes during pregnancy. In this prospective study, we followed women during pregnancy (total = 123 of which secretors = 108, non-secretors = 15) and characterised their gut microbiota by quantitative polymerase chain reaction (qPCR), Fluorescence In situ Hybridisation (FISH), Denaturing Gradient Gel Electrophoresis (DGGE) and pyrosequencing. qPCR revealed that <i>C</i>. <i>coccoides group</i> counts decreased significantly in non-secretors in comparison to secretors (p = 0.02). Similar tendency was found by FISH analysis in <i>Clostridium histolyticum</i> and <i>Lactobacillus-Enterococcus</i> groups between the secretor and the non-secretor pregnant women. DGGE analysis showed significant decrease in richness of <i>Clostridium</i> sp. between secretor and non-secretor mothers during pregnancy. Pyrosequencing based analysis at phyla level showed that there is greater increase in Actinobacteria in secretors in comparison to non-secretors, whereas Proteobacteria showed more increase in non-secretors. Change in relative abundance of <i>Clostridiaceae</i> family from first to third trimester were significantly associated with secretor status of pregnant women (p = 0.05). Polyphasic approach for microbiota analysis points out that the host secretor status (FUT2 genotype) affects the gut microbiota during pregnancy. This may lead to altered infant gut microbiota colonization.</p></div>