Table 1. Main characteristics of included studies in this meta-analysis.

Author	Year	Country	Ethnicity	Genotyping methods	Mean age (year ± median)		Sample size		HWE test	Quality score
					Cases	Controls	Cases	Controls
Jing Li [24]	2014	China	Asian	Taqman	40.34 ± 17.85	28.65 ± 9.15	200	100	Y	9
L.M. Gomez [19]	2007	Colombia	Latin American	Taqman	40 ± 16	43 ± 16	223	134	Y	8
Shou-Gang Kuai [20]	2015	China	Asian	Taqman	48.4 ± 10.5	48.4 ± 10.5	47	50	Y	9
Yanlin Li and Yuan Tao [21]	2012	China	Asian	Taqman	43.8 ± 5.76	40.2 ± 4.9	215	245	Y	8
Yanlin Li and Zhaofang Zeng [22]	2012	China	Asian	Taqman	47.8 ± 5.76	40.2 ± 4.9	151	149	Y	8

Abbreviation: Y, Yes.