The present comprehensive meta-analysis identified stronger association (P = 3×10−56) than the previous studies (Luczak et al. 2006; Zintzaras et al. 2006), which can be explained by several differences besides different research purposes and statistical methods (Minelli et al. 2005; Trikalinos et al. 2008; Zintzaras 2008 ; Zintzaras and Lau 2008; Zintzaras et al. 2009; Zintzaras et al. 2008) from ours (Li and He 2007a, b, c, 2008): the meta-analysis by Zintzaras et al.(Zintzaras et al. 2006) a) included 23 studies published in or before 2004 (compared to 53 studies in our meta-analysis); b) only included English literature; c) provided OR without specific P values; and d) found no association with liver disease using allelic analysis (the result was only positive under the dominant model). Another meta-analysis by Luczak et al.(Luczak et al. 2006), in which the latest dataset was also published in 2004, a) included 22 Asian studies including 1,980 cases and 2,550 controls (we included 9,678 cases and 7,331 controls); b) performed genotypic analysis but not allelic analysis; c) provided no specific P values; d) reported negative results
