Table 2. Genotypes distribution of MTR A2756G polymorphism in cases and controls.

Reference	Sample size		Case group					Control group
	Case	Control	AA	AG	GG	A	G	AA	AG	GG	A	G	PHWE
de Jonge et al. [23]	245	489	162	74	9	398	92	340	137	12	817	161	0.68
Gast et al. [24]	446	547	280	153	13	713	179	375	151	21	901	193	0.24
Kamel et al. [25]	87	306	55	29	3	139	35	194	97	15	485	127	0.53
Lautner-Csorba et al. [26]	543	529	344	175	24	863	223	341	163	25	845	213	0.34
Lightfoot et al. [27]	870	759	531	288	51	1350	390	510	223	26	1243	275	0.79
Metayer et al. [28]	376	447	237	123	16	597	155	292	137	18	721	173	0.70
Milne et al. [29]	391	514	251	130	10	632	150	337	158	19	832	196	0.93
Petra et al. [30]	68	258	51	16	1	118	18	161	82	15	404	112	0.30
Rahimi et al. [31]	73	128	42	26	5	110	36	75	47	6	197	59	0.69
Nikbakht et al. [32]	125	100	74	44	7	192	58	58	35	7	151	49	0.59

Abbreviations: HWE, Hardy–Weinberg equilibrium; MTR, methionine synthase.