we analyze a cohort of mothers and infants with a metatrancriptomic approach, in order to capture the temporal development of gene expression patterns in the gut microbiota community throughout the first year of life. In addition, we analyze the gut microbiota in the mothers of the infants at two points in time, i. e. days before delivery and one year after delivery. These analyses allow us to establish stage-specific patterns of expression of gut microbiome functions.