a Estimated time in ‘Million years ago’ (Mya) based on the time when the repetitive element subfamily appeared in the human genome.
b Approximate ratio of the observed to the expected CpG content (CpGo/e) of the sequence. CpG observed/expected (CpGo/e). The ratio is calculated using the formula ((Num of CpG/(Num of C × Num of G)) × Total number of nucleotides in the sequence).
c Mean methylation of all low-exposure control groups from Study 1, Study 2, and Study 3.