Figure 1. Hypomethylation and hypermethylation of human genome. (A) In normal cells, cytosine and guanine dinucleotides (CpG) islands in the promoter region are unmethylated. (B) In cancer cells, promoter hypomethylation of oncogenic genes lead to transcription initiation. (C) Promoter hypermethylation of tumor suppressor genes lead to gene silencing. (D) Global hypomethylation affects gene integrity and stability.
