. 2009 Nov 13;101(2):300–305. doi: 10.1111/j.1349-7006.2009.01434.x

Table 1.

Comparison between mutations and DNA methylation

	Mutation	DNA methylation	References
Number of alterations per cancer cell	∼80	Several hundred to 1000	⁽ 18, 23, 27, 28, 29, 30 ⁾
Frequency of alterations of a specific gene in non‐cancerous tissues	10⁻⁵/cell, up to 10⁻³/cell	0.1 to several % up to several 10% of cells	⁽ 44, 46 ⁾
Inducers	Mutagenic chemicals, radiation, oxygen radical	Chronic inflammation, aging	⁽ 45, 56 ⁾
Target gene	Random	Specific	⁽ 18, 27, 37, 61 ⁾
Reversibility	Irreversible	Reversible	⁽ 18, 61, 70, 71, 72, 73 ⁾

Detailed explanations are in individual sections.