Table 2. NOS3 G894T genotype distribution among AD cases and controls in the included studies.

First author	Cases			Controls			Pa (HWE)
	G/G	G/T	T/T	G/G	G/T	T/T
Dahiyat M -1	136	103	21	80	112	15	0.004
Dahiyat M -2	95	76	8	74	91	21	0.376
Crawford F	129	134	24	61	49	10	0.971
Higuchi S	350	57	4	297	52	1	0.416
Emahazion T	48	59	14	70	68	14	0.664
Kalman J	30	15	6	22	29	0	0.005
Kunugi H	149	23	0	143	21	1	0.812
Monastero R	62	77	10	65	76	8	0.017
Sanchez-Guerra M	97	154	50	101	145	63	0.408
Singleton A	88	96	28	43	53	10	0.269
Tedde A	91	106	23	38	42	15	0.554
Akomolafe A -1	193	42	0	56	25	1	0.326
Akomolafe A -2	109	119	31	61	55	11	0.778
Blomqvist ME	199	145	38	81	77	12	0.270
Guidi I	210	154	41	110	120	23	0.228
Yang Z	56	11	1	121	36	1	0.334
Zhou Y	441	77	12	495	92	14	<0.001
Li H	285	316	87	292	322	67	0.108
Styczynska M	106	38	10	100	60	16	0.120
Wang B	296	40	2	299	76	3	0.441
Azizi Z	67	30	3	54	44	2	0.039
Ferlazzo N	28	29	12	33	25	11	0.108
Giedraitis V	37	36	6	183	148	30	0.992

HWE: Hardy-Weinberg equilibrium.

^aP value for HWE test in controls.