Table 1.

Distribution of selected characteristics in the study subjects

	Cases No.(%)				Controls No.(%)
	Gastrointestinal cancer	Gastric cancer	Colon cancer	Rectal cancer
No. of subjects	296	90	93	103	448
Gender
Male	169(57.09)	64(71.11)	48(51.61)	57(50.44)	223(49.78)
Female	127(42.91)	26(28. 89)	45(48.39)	56(49.56)	225(50.22)
Age
Mean ± SD	61.76 ± 9.92	64.68 ± 9.01	61.59 ± 8.87	59.57 ± 10.89	60.67 ± 10.92
Smoking
No	156(52.70)	33(36.67)	53(56.99)	70(61.95)	269(60.04)
Yes	140(47.30)	57(63.33)	40(43.01)	43(38.05)	179(39.96)
Drinking
No	202(68.24)	56(62.22)	65(69.89)	81(71.68)	322(71.88)
Yes	94(31.76)	34(37.78)	28(30.11)	32(28.32)	126(28.13)
Family history
No	212(71.62)	68(75.56)	68(73.12)	76(67.26)	338(75.45)
Yes	84(28.38)	22(24.44)	25(26.88)	37(32.74)	110(24.55)
H-RAS T81C
TT	204(68.92)	48(53.33)	71(76.34)	85(75.22)	355(79.24)
TC	88(29.73)	40(44.44)	20(21.51)	28(24.78)	89(19.87)
CC	4(1.35)	2(2.22)	2(2.15)	0(0.00)	4(0.89)
Allele frequencies
T	496(83.78)	136(75.56)	162(87.10)	198(87.61)	799(89.17)
C	96(16.22)	44(24.44)	24(12.90)	28(12.39)	97(10.83)