Table 1. Data summery of the found articles.
Study	Witt et al., 2004		Wang et al., 2007		Hong et al., 2008		Hiby et al., 2008		Vargas et al., 2009		Faridi et al., 2009		Khosravifar et al., 2011		Ozturk et al., 2012		Djulejic et al., 2015		Dambaeva et al., 2016		Our original study
Gene	RSA N=52	Control N=55	RSA N=73	Control N=68	RSA N=16	Control N=41	RSA N=95	Control N=269	RSA N=68	Control N=68	RSA N=205	Control N=224	RSA N=100	Control N=100	RSA N=40	Control N=90	RSA N=25	Control N=122	RSA N=139	Control N=195	RSA N=100	Control N=100
2DL1	52	55	73	68	8	21	92	258	63	64	141	215	97	95	40	89	24	115	135	189	93	95
p value (ED) a	1 (FET) b		1 (FET)		0.841 (-)		0.769 (FET) (-)		0.999 (FET) (-)		0.0001 (-)		0.720 (+)		1 (FET)		1 (FET)		1 (FET)		0.764 (-)
2DL2	29	23	22	23	16	22	45	137	43	37	110	111	52	58	26	41	17	72	69	96
p value (ED)	0.211 (+)		0.777 (-)		0.002 (+)		0.361 (-)		0.383 (+)		0.446 (+)		0.475 (-)		0.632 (+)		0.537 (+)		1
2DL3	47	47	72	67	6	18	88	245	58	58	169	187	87	85	37	74	24	110	124	172
p value (ED)	0.631 (+)		1 (FET)		0.887 (-)		0.806 (+)		1 (FET)		0.887 (-)		0.841 (+)		0.207 (+)		0.469 (FET) (+)		0.920 (+)
2DL4
2DL5	16	20	35	28	5	12	36	148	37	33	127	151			32	56	4	50	79	103	58	60
pvalue (ED)	0.680 (-)		0.521 (+)		1 (FET)		0.005 (-)		0.610 (+)		0.238 (+)				0.072 (+)		0.032 (-)		0.537 (+)		0.887 (-)
3DL1	50	48	73	67			88	256	64	63	120	191			36	81	24	117	125	185	93	95
pvalue (ED)	0.162 (FET) (+)		1 (FET)				0.502 (-)		0.999 (FET) (+)		0.0001 (-)				1 (FET)		1 (FET)		0.131 (-)		0.764 (-)
3DL2
3DL3
2DS1	21	25	44	28	1	4	24	121	32	26	92	88	35	48	21	31	8	58	63	73	49	40
p value (ED)	0.740 (-)		0.035 (+)		1 (FET)		0.001 (-)		0.386 (+)		0.283 (+)		0.084 (-)		0.005 (+)		0.228 (-)		0.182 (+)		0.254 (+)
2DS2	27	26	22	18	1	3	46	140	45	39	104	72	50	58	26	41	14	69	69	97	59	54
p value (ED)	0.777 (+)		0.764 (+)		1 (FET)		0.624 (-)		0.377 (+)		0.001 (+)		0.319 (-)		0.063 (+)		0.806 (+)		1		0.565 (+)
2DS3	16	15	25	20	2	3	22	70	22	24	94	66			17	29	11	40	44	55	38	34
p value (ED)	0.824 (+)		0.622 (+)		0.613 (+)		0.680 (-)		0.862 (-)		0.0007 (+)				0.350 (+)		0.399 (+)		0.577 (+)		0.654 (+)
2DS4	18	21	72	65	8	24	90	255	62	64	109	163			36	82	25	117	130	185	95	95
p value (ED)	0.862 (-)		0.352 (FET) (+)		0.777 (-)		1 (FET)		0.740 (-)		0.0001 (-)				1 (FET)		0.588 (FET) (+)		0.777 (-)		1
2DS5	10	18	38	26	4	8	23	102	30	19	122	122			22	35	6	37	53	70	35	34
p value (ED)	0.171 (-)		0.139 (+)		0.722 (FET) (+)		0.021 (-)		0.074 (+)		0.337 (+)				0.129 (+)		0.698 (-)		0.764 (+)		1
3DS1	17	20	38	32			24	121	34	23	162	116			16	37	7	46	62	77	41	40
p value (ED)	0.590 (-)		0.761 (+)				0.001 (-)		0.082 (+)		0.0001 (+)				0.920 (-)		0.488 (-)		0.409 (+)		1
2DP1
3DP1
Study design	Case-control		Case-control		Case-control		Case-control		Case-control		Case-control		Case-control		Case-control		Case-control		Cohort for KIR2DS1		Case-control
Genotyping method	PCR-SSP		PCR-SSP		PCR-SSP		PCR-SSP		PCR-SSO		PCR-SSP		PCR-SSP		PCR-SSO		PCR-SSP		PCR-SSO		PCR-SSP
RSA definition	3 spontaneous abortion		3 spontaneous abortion		3 spontaneous abortion		3 spontaneous abortion		3 spontaneous abortion		3 spontaneous abortion		3 spontaneous abortion		A history of miscarriage		Any fertility problem		2 spontaneous abortion		3 spontaneous abortion
Control definition	2 history of normal delivery		2 history of normal delivery		2 history of normal delivery		Any primiparous woman		2 history of normal delivery		2 history of normal delivery		1 history of normal delivery		2 history of normal delivery		Not mentioned		Not mentioned		2 history of normal delivery
Place	Brazil		China		China		London		Brazil		India		Iranian		Mediterranean		Albania		America		Iran
Ethnicity	Caucasian		Chinese		Chinese		Caucasian		Caucasian		Indian		Caucasian		Caucasian		Caucasian		Caucasian		Caucasian
Study number in dendrogram	1		2		3		4		5		6		7		8		9		10		11
a) ED stands for effect direction; the positive ones show risk factors and the negative ones show protecting factors.b) FET stands for Fisher's exact test.