Table 1.

Correlation between methylation of p16 gene and age, enzyme cutting site of normal clonic mucosa

	Number of site	Full methylation	Partial methylation	Un-methylation
Age (yrs)
≤ 40	33	4	3	26a
41-60	60	19	8	33
> 60	87	23	8	56
Site
Hpa-II	60	13	7	40b
Sac-II	60	28	8	24
Sma-I	60	5	4	51

^a0.1 > P > 0.05,

^bP < 0.005.