Table 3.

Average methylation levels of VDAC genes across different normal human and murine samples from single-based resolution methylomes (SRMs) provided by MethBank (v.4.1).

Gene	Brain	Muscle	Heart	Digestive system	Placenta
Average methylation levels of VDAC promoters (β-value of 0–1)
hVDAC1	0.26	0.23	0.24	0.22	0.31
hVDAC2	0.63	0.62	0.61	0.57	0.52
hVDAC3	0.42	0.42	0.40	0.35	0.32
Gene	2-cell	4-cell	E13	E6.5	E7.5	ICM	Oocyte	Sperm
mVDAC1	0.11	0.08	0.01	0.08	0.12	0.03	0.07	0.01
mVDAC2	0.48	0.41	0.02	0.19	0.25	0.17	0.69	0.2
mVDAC3	0.05	0.02	0.01	0.09	0.11	0.01	0.01	0.07

Methbank (http://bigd.big.ac.cn/methbank) contains the SRM profiles from a wide range of cell/tissue lines in human and from mouse embryonic development stages. According to MethBank, the promoter region is defined as the region 2000 bp upstream of transcription start site (TSS) for animals. Furthermore, the average methylation data are calculated as β-Value that reflects the methylation intensity at each CpG site. β-Values of 0–1 (represented from 0 to 1) indicate signifying percent methylation, from 0 to 100%, respectively, for each CpG site (Dhas et al., 2015). We specifically selected human and mouse SRMs of the methylation level in the VDAC gene promoter. On the left, the human SRM profiles of tissues associated with the specific expression pattern of VDAC genes as discussed in Zinghirino et al. (2020) are shown.