MiR-146a rs2910164 polymorphism increases risk of gastric cancer: A meta-analysis

Table 1 Characteristics of all studies included in the meta-analysis

Study	Year	Country	Ethnicity	Source of controls	Genotyping method	Cases (n)	Control (n)	Quality score	HWE, P value
Zeng et al[23]	2010	China	Asian	HB	PCR-RFLP	304	304	15	0.12
Okubo et al[22]	2010	China	Asian	HB	PCR-RFLP	552	697	15	0.28
Hishida et al[21]	2011	China	Asian	HB	TaqMan	583	1637	15	0.74
Zhou et al[24]	2012	China	Asian	HB	TaqMan	1686	1895	15	0.93
Ahn et al[20]	2012	China	Asian	PB	PCR-RFLP	461	447	16	0.36
Dikeakos et al[18]	2013	Greek	Caucasian	PB	PCR-RFLP	163	480	15	0.29
Kupcinskas et al[19]	2014	Germany	Caucasian	HB	TaqMan	363	351	11	0.44

HB: Hospital-based; HWE: Hardy-Weinberg equilibrium; PB: Population-based; PCR-RFLP: Polymerase chain reaction-restriction fragment length polymorphism.

Table 2 Pooled results for overall and stratified meta-analyses of the miR-146a polymorphism

Contrast	Overall or subgroup	Comparisons (n)	OR (95%CI)	P value	I2
G vs C	Overall	7	1.07 (0.94-1.22)	0.32	74%
	Asian	5	1.05 (0.89-1.24)	0.54	82%
	Caucasian	2	0.99 (0.72-1.38)	0.97	0%
	High quality	6	1.05 (0.91-1.22)	0.48	78%
	Large sample size	3	0.98 (0.78-1.24)	0.89	90%
	Small sample size	4	1.16 (1.03-1.30)	0.01	0%
GG vs CC	Overall	7	1.14 (0.88-1.49)	0.31	69%
	Asian	5	1.11 (0.81-1.51)	0.51	79%
	Caucasian	2	1.33 (0.80-2.21)	0.27	0%
	High quality	6	1.15 (0.86-1.53)	0.34	74%
	Large sample size	3	0.99 (0.63-1.57)	0.97	88%
	Small sample size	4	1.33 (1.03-1.73)	0.03	0%
GG vs GC	Overall	7	1.14 (1.03-1.27)	0.01	19%
	Asian	5	1.11 (0.99-1.25)	0.06	24%
	Caucasian	2	1.36 (1.01-1.85)	0.04	0%
	High quality	6	1.12 (1.01-1.26)	0.04	26%
	Large sample size	3	1.06 (0.84-1.33)	0.64	60%
	Small sample size	4	1.19 (0.97-1.47)	0.10	0%
GC vs CC	Overall	7	1.03 (0.87-1.21)	0.76	56%
	Asian	5	0.88 (0.62-1.25)	0.48	0%
	Caucasian	2	1.06 (0.87-1.28)	0.58	68%
	High quality	6	1.03 (0.87-1.23)	0.71	62%
	Large sample size	3	0.97 (0.77-1.21)	0.76	73%
	Small sample size	4	1.12 (0.93-1.36)	0.22	40%
GG vs GC + CC	Overall	7	0.03 (-0.01-0.07)	0.18	54%
	Asian	5	0.02 (-0.03-0.06)	0.54	66%
	Caucasian	2	0.07 (-0.00-0.14)	0.06	0%
	High quality	6	0.02 (-0.02-0.07)	0.36	60%
	Large sample size	3	0.00 (-0.07-0.08)	0.94	83%
	Small sample size	4	0.05 (0.00-0.10)	0.03	0%
GG + GC vs CC	Overall	7	1.06 (0.88-1.28)	0.53	69%
	Asian	5	1.08 (0.86-1.35)	0.52	29%
	Caucasian	2	0.98 (0.72-1.38)	0.97	0%
	High quality	6	1.06 (0.87-1.30)	0.55	75%
	Large sample size	3	1.18 (0.98-1.40)	0.07	23%
	Small sample size	4	0.97 (0.72-1.31)	0.87	86%

Large sample size: > 1000; Small sample size < 1000.

Table 3 Egger’s linear regression tests for funnel plot asymmetries

Group	P value
	G vs C	GG vs CC	GG vs GC	GC vs CC	GG vs GC + CC	GG + GC vs CC
Overall	0.712	0.742	0.902	0.823	0.961	0.689
Asian	0.519	0.452	0.181	0.764	0.975	0.266
High quality	0.607	0.767	0.830	0.944	0.964	0.672