Supplementary_Files_Maternal_Methionine_Supplementation.xlsx

Whole-genome bisulfite sequencing (WGBS) was performed on oocytes collected from 16 twin ewe pairs (8 methionine-treated and 8 controls). These ewes were later bred to control rams, and embryos were flushed for WGBS as well. In oocytes, 2,056 differentially methylated cytosines (DMCs) were identified. Additionally, 17 mitochondrial DMCs were identified, with 12 hypermethylated and 5 hypomethylated. In embryos, 113 DMCs were identified. Mitochondrial DNA analysis revealed 22 hypermethylated DMCs. To assess the inheritance of methyl marks, we compared DMCs between oocytes and embryos. While no direct overlaps were found in nuclear DNA, 3 CpGs exhibited opposite methylation trends—hypomethylated in oocytes but hypermethylated in embryos. In contrast, 5 mitochondrial DMCs overlapped between oocytes and embryos.