A recent study, published in Genome Biology, shows that there are substantially more paternally expressed genes in the endosperm of the plant Arabidopsis than what has previously been identified. This indicates that paternal-specific gene expression is of higher functional relevance than previous estimates.

Genomic imprinting is an epigenetic phenomenon causing maternal and paternal alleles to be differentially expressed after fertilization. Imprinted genes are epigenetically modified during gamete – egg or sperm – formation, and the established epigenetic asymmetry is maintained after fertilization.

The researchers hypothesize that the common use of the protein group PRC2 and methylation of the lysine H3K9 to silence targets during reproduction has convergently evolved in flowering plants and mammals to ensure stable silencing during this sensitive life stage.

Samples were sequenced at the National Genomic Infrastructure (NGI) at SciLifeLab Uppsala.