Researchers from France, the US, and Singapore describe cytosine hydroxymethylation (5hmC) modifications that appear to coincide with gene expression in the malaria-causing parasite Plasmodium falciparum. Using enzyme-linked immunosorbent assays, RNA sequencing, hydroxymethylated DNA-immunoprecipitation sequencing, mass spec, and other approaches, the team saw 5hmC levels that appeared to outpace cytosine methylation levels in the parasite's asexual life stage.