Methylation patterns for parents and offspring
Of the 1,854 DMCs identified between parental environments, 724 (39.05%) maintained the same methylation profile (either hyper or hypomethylated relatively to the other environment) in the offspring reared in an environment matching their parent, but changed in the offspring reared in a mismatching environment and were classified as environmentally-induced epialleles. Of the remaining 1,130 DMCs, 98 (5.28% of the total) maintained the parental methylation patterns in the offspring regardless of their own rearing environment, of which five (scaffold: NW_016094248.1, position: 1049469; scaffold: NW_016094269.1., position: 1135514; scaffold: NW_016094316.1, position: 636543; scaffold: NW_016094324.1, position: 879262; scaffold: NW_016094376.1, position: 917192) had less than 10% change in methylation score across all experimental groups (classified as potentially intergenerational) (Table 1). Three of the five DMCs which maintained the parental methylation patterns on the offspring were significantly influenced by parental environment (Table 2; Fig. 3).
When analysed separately by environment-specific context, 30 DMCs in the offspring originated from enriched environment, and 19 in the offspring originated from poor environment maintained their methylation score relatively to its parents regardless of the offspring environment within less than 10% change.