Replication study in Chinese Han population and meta-analysis supports association between the MBL2 gene polymorphism and HIV-1 infection.

Mannose-binding lectin (MBL) plays an important role in immunity to HIV-1 infection. The exon1 coding polymorphisms of the MBL2 gene have been implicated in the susceptibility to HIV-1 infection, but the results were controversial. In the present study, a case-control study in a Chinese population was conducted to replicate the association, and then a meta-analysis combing our new data and published data was performed to clarify these findings. In total, 15 studies consisting 2219 HIV-1 patients and 2744 controls were included. Odds ratios (ORs) with 95% confidence intervals (95% CIs) were assessed in the main analyses. By dividing the controls into two groups, healthy controls and HIV-1 exposed but seronegative (HESN) controls, we explored different genetic models and allelic model to detect the association. By using the healthy controls, we found that the MBL2 exon 1 polymorphisms were associated with hosts' susceptibility to HIV-1 infection in dominant model (p=0.01, 95% CI 1.05-1.43), recessive model (p<0.0001, 95% CI 1.35-2.28), allelic model (p<0.0001, 95% CI 1.12-1.37) and O/O vs. A/A model (p<0.00001, 95% CI 1.40-2.38). In the subgroup analysis by ethnicity, significant elevated risks were found in Caucasians (recessive model: p<0.0001, 95% CI 1.36-2.51), but not in Asians (recessive model: p=0.10, 95% CI 0.91-2.77). Collectively, our findings from our case-control replication study and meta-analysis suggested that the MBL2 gene exon 1 coding variants were associated with hosts' susceptibility to HIV-1 infection, especially in Caucasians, but not in Asians.