Chemokine receptor 5 (CCR5) delta 32 polymorphism in lupus nephritis: A large case-control study and meta-analysis

Abstract

Objectives: Recent animal experiments showed that CCR5-deficient lupus mice (CCR5^−/−) were closely associated with aggravated lupus nephritis. CCR5 Δ32 variation, a nonsynonymous mutation of CCR5, resulted in altered CCR5 function. However, the CCR5 Δ32 mutation in human lupus nephritis has been rarely reported in the literature. Methods: A large case-control study that included 2010 samples from a Chinese population was conducted, followed by a meta-analysis combining the current and previously published studies to explore the effect of CCR5 Δ32 on lupus nephritis susceptibility. Results: Four CCR5 Δ32 heterozygote carriers were detected in lupus nephritis patients only. We detected no CCR5 Δ32 homozygotes in our study population. In the meta-analysis, including 1,092 cases and 2,229 controls, we found great heterogeneity between studies (p < 0.001, I²= 89.6%). Furthermore, stratified and sensitivity analyses suggested that ethnicity and CCR5 Δ32 allele frequency were the main origin of heterogeneity. In the subgroups without obvious heterogeneity, we observed a positive correlation between CCR5 Δ32 and lupus nephritis risk (p < 0.05). Conclusions: Our study confirmed that the CCR5 Δ32 mutation is a very rare variation found in the Chinese population with Han ethnicity. However, CCR5 Δ32 might play a role in lupus nephritis susceptibility. Future replications and functional studies are needed.

• Chinese Han ethnicity
• complex autoimmune disease
• functional genetic variant
• susceptibility
• systemic lupus erythematosus