Identification of age-related CpG sites from longitudinal avian methylomes

Sex chromosomes are thought to play an important role in sex-dependent ageing, yet they are neglected in epigenetic aging research. We identified genome-wide age-related CpG (AR-CpG) sites in two avian species (zebra finch and jackdaw) and found AR-CpG sites to be overrepresented on the haploid, female-specific W chromosome in both species, and on the Z chromosome in the zebra finch.