Dear Editor,
DNA methylation is a key epigenetic regulatory approach for many biological processes,such as genomic imprinting,epigenetic memory maintenance,aging,and neural devel-opment.In addition to 5-methylcytosine,DNA methylation at N6-deoxyadenosine (N6-mA) is the most prevalent DNA modification in prokaryotes[1].With the advances in various deep sequencing techniques,recent studies have started to find N6-mA in eukaryotes,including humans androdents [2-7].