SLC11A1 Polymorphisms and TB Figure 1. Flow diagram of study identification. doi:10.1371/journal.pone.0015831.g001 identified, and full-text article retrieve excluded 11 of them (please refer to Table S1 for more detailed information). Finally, 38 studies from 36 articles, 29 in English [7,9–36]and 7 in Chinese [37–43], were included in this review and meta-analysis. As shown in Table S2 and Table S3, among the included articles, 25 were conduced in Asians and 11 in non-Asians (3 from Africa, 4 from Europeans and 2 from Americans). Thirteen studies and 3 studies specifically addressed pulmonary TB and extra- pulmonary TB, respectively. Seven studies were population based. HIV status of the studied population was considered in 24 studies. There were 13 studies matched controls with cases for major covariates (age, sex, ethnicity, and area of residence). For 39 UTR, D543N, INT4 and 59 (GT)n, meta-analyses were conduced within 30, 29, 20 and 12 studies, respectively. Figure 2 shows the associations between SLC11A1 39 UTR polymorphism and TB. Meta-analysis suggested that TGTG- carriage (TGTG2/2 and TGTG2/+) might be a risk factor for TB with a summarized OR of 1.35 (95%CI, 1.17–1.54) as compared to TGTG+/+ genotype. Medium heterogeneity between studies (p,0.01; I2 = 48.41%) was observed. No evident publication bias was found (p = 0.99 for Begg rank correlation analysis; p = 0.59 for Egger weighted regression analysis). In the stratified analysis, the strength of the association was most evident for Asians, and marginal results were observed for Africans and Westerns. No pronounced difference was found according to different study base. As shown in Figure 3, good homogeneity was observed between studies addressing D543N polymorphism (p,0.01; I2 = 61.26%) and A allele carriage was significantly associated with TB (OR, 1.24; 95% CI, 1.04–1.49). No substantial publication bias was observed (p = 0.39 for Begg rank correlation analysis; p = 0.49 for Egger weighted regression analysis). In the subgroup analyses, significant relations were observed for Africans and Westerns. As shown in Figure 4, a significant association was found for INT4 C allele carriage (CC+CG) with increased risk of TB as compared to GG genotype (OR, 1.23; 95% CI, 1.04–1.44). Medium heterogeneity between studies (p = 0.08; I2 = 32.47%) was observed. No significant publication bias was observed (p = 0.12 for Begg rank correlation analysis; p = 0.35 for Egger weighted regression analysis). The association was not significant any more in Westerns in the subgroup analysis. Meta-analysis of the association between TB and SLC11A1 59 promoter (GT)n polymorphism was shown in Figure 5. As compared to the most commonly distributed allele 3, carriage of other alleles was significantly related to an increased risk of TB with a summarized OR of 1.31 (95%CI, 1.08–1.59). No substantial heterogeneity was observed between studies (p,0.01; I2 = 61.78%). No publication bias was found (p = 0.49 for Begg rank correlation analysis; p = 0.51 for PLoS ONE | www.plosone.org 2 January 2011 | Volume 6 | Issue 1 | e15831