Indication of family-specific DNA methylation patterns in developing oysters

The roles of DNA methylation during invertebrate development remain enigmatic, especially regarding the inheritance and ontogenetic dynamics of methylation. Here, we characterized the genome-wide methylome of Crassostrea gigas sperm and larvae from two full-sib families nested within a maternal half-sib family across several developmental stages. Our data suggest that DNA methylation patterns are inherited, as methylation patterns were similar between the two sires and their offspring. Loci differing between the two paternal full-sib families (189) were found throughout the genome but were concentrated in transposable elements. We suggest that the predominance of differentially methylated loci within transposable elements is a result of selection against changes in gene body methylation. Introduction DNA methylation is an epigenetic modification that is ubiquitous across many eukaryotes, with variable patterns and functions across taxa. This epigenetic mechanism involves the addition of a methyl group to cytosines, usually in CpG dinucleotides, . CC-BY 4.0 International license peer-reviewed) is the author/funder. It is made available under a The copyright holder for this preprint (which was not . http://dx.doi.org/10.1101/012831 doi: bioRxiv preprint first posted online Dec. 16, 2014;