DNA methylation in early developmental stages and adult tissues. (A) Global DNA methylation level of genomic DNA from unfertilized eggs, embryonic stages and adult tissues were determined by an enzyme-linked immunosorbent assay specific for methylated DNA. Error bars indicate standard deviation (n = 3) (B) Bisulfite sequencing of EF-1α gene body region. Examined selected stages and tissues are noted above boxes. The sequencing results from eight to thirteen clones are shown in boxes. Each horizontal line represents the sequencing result of one subclone. Methylated CpG sites are shown as solid circles, and open circles indicate unmethylated CpG sites.