Poor nutrition during pregnancy stunts the growth of young mice by modifying their gene expression.

Michelle Holland and Vardhman Rakyan at Queen Mary University of London and their colleagues fed female mice diets containing either 8% or 20% protein throughout pregnancy and until weaning. They analysed patterns of methylation — which can influence gene expression — on the DNA of the rodents' offspring.

Pups from mothers fed the low-protein diet were, on average, 25% smaller at weaning. This effect was further influenced by variation within an animal's many gene copies for ribosomes, the cell's protein-construction machines. The extent of growth restriction depended on the proportion an individual had of a particular gene variant.

Studying the effects of methylation and other chemical marks on ribosomal genes may shed light on some human diseases, the authors say.

Science http://doi.org/bk5b (2016)