Table 1. Characteristics of selected studies in the meta-analysis.

Study (year)	Country	Genotyping method	Ethnicity	Sample size (case/control)
Battiloro (2000) [17]	Italy	PCR	Caucasian	256/806
Deng (2004) [28]	China	PCR	Mongoloid	88/119
Diaz (2000) [18]	Colombia	PCR	Latina	29/188
Downer (2002) [24]	USA	PCR-RFLP	Mixed	929/445
Grimaldi(2002)[13]	Brazil	PCR	Mixed	113/549
Li (2003) [26]	China	PCR	Mongoloid	94/46
Liu (2004) [20]	USA	PCR	Mixed	316/513
Lockett (1999) [19]	Britain	PCR	Mixed	86/105
Oh(2008)[8]	German	PCR	Caucasian	610/427
			African	35/26
Papa (2000) [10]	Greece	PCR	Caucasian	138/239
Paz-y-Mino (2005) [27]	Ecuador	PCR	Latina	295/50
Philpott (2003) [12]	USA	PCR-RFLP	Mixed	2047/558
Takacova (2008) [22]	Slovakia	PCR	Caucasian	162/198
Tan (2010) [16]	China	PCR	Mongoloid	250/237
Tang (2010) [25]	China	PCR-LDR	Mongoloid	245/223
Trecarichi(2006)[11]	Italy	PCR	Caucasian	120/120
Veloso(2010)[23]	Span	PCR	Caucasian	184/236
Wang (2003) [21]	China	PCR	Mongoloid	330/474