Polymorphisms of DNA repair genes XRCC1 and XRCC3, interaction with environmental exposure and risk of chronic gastritis and gastric cancer

Table 3 Association of heterozygous and mutant homozygous to the polymorphisms of codons 194 and 399 of the XRCC1 gene and to the codon 241 of the XRCC3 gene with demographic and environmental risk factors in chronic gastritis (CG) and gastric cancer (GC) patients and the respective control groups C1 and C2

	Groups	Variable
		Gender		Smoke		Drink		H pylori infection
		Male	Female	No	Yes	No	Yes	Positive	Negative
		n (%)	n (%)	n (%)	n (%)	n (%)	n (%)	n (%)	n (%)
XRCC1	CG	11 (42.3)	15 (57.7)	9 (34.6)	17 (65.4)	20 (77)	6 (23)
Arg194Trp
+	C1	10 (52.6)	9 (47.4)	13 (68.4)	6 (31.6)	17 (89.5)	2 (10.5)
Trp194Trp		P = 0.4929		P = 0.0250		P = 0.4355
XRCC1	CG	55 (53)	49 (47)	48 (46.2)	56 (53.8)	71 (68.3)	33 (31.7)	45 (53.6)	39 (46.4)
Arg399Gln	GC	67 (77)	20 (23)	24 (27.6)	63 (72.4)	35 (40.2)	52 (59.8)	9 (23.7)	29 (76.3)
+		P = 0.0005		P = 0.0084		P = 0.0001		P = 0.0021
Gln399Gln	CG	55 (52.9)	49 (47.1)	48 (46.2)	56 (53.8)	71 (68.3)	33 (31.7)
	C1	52 (48.5)	55 (51.4)	68 (63.6)	39 (36.4)	91 (85)	16 (15)
		P = 0.5335		P = 0.0111		P = 0.0039
	GC	67 (77)	20 (23)	24 (27.6)	63 (72.4)	35 (40.2)	52 (59.8)
	C2	56 (70)	24 (30)	46 (57.5)	34 (42.5)	63 (78.8)	17 (21.2)
		P = 0.3042		P = 0.0001		P = 0.0000
XRCC3	CG	57 (51.8)	53 (48.2)	46 (41.8)	64 (58.2)	77 (70)	33 (30)	44 (52.4)	40 (47.6)
Thr241Met	GC	59 (77.6)	17 (22.4)	21 (27.6)	55 (72.4)	36 (47.4)	40 (52.6)	10 (28.6)	25 (71.4)
+		P = 0.0004		P = 0.0494		P = 0.0019		P = 0.0175
Met241Met	CG	57 (51.8)	53 (48.2)	46 (41.8)	64 (58.2)	77 (47.4)	33 (52.6)
	C1	59 (50)	59 (50)	75 (63.6)	43 (36.4)	98 (79.6)	20 (20.4)
		P = 0.7838		P = 0.0010		P = 0.0110
	GC	59 (77.6)	17 (22.4)	21 (27.6)	55 (72.4)	36 (47.4)	40 (52.6)
	C2	59 (71.1)	24 (28.9)	42 (50.6)	41 (49.4)	66 (79.6)	17 (20.5)
		P = 0.3458		P = 0.0031		P = 0.0000