Association between the CD24 Ala57Val polymorphism and risk for multiple sclerosis and systemic lupus erythematosus: a meta-analysis

The cluster of differentiation 24 (CD24) Ala57Val polymorphism has been implicated as a risk factor for multiple sclerosis (MS) and systemic lupus erythematosus (SLE); however, genetic studies have produced controversial results. A meta-analysis was performed on this topic. We used odds ratio (OR) and 95% confidence interval (95% CI) to investigate the strength of association. Eleven studies from nine publications consisting of 2466 cases and 2650 controls were included. The results suggested that the CD24 Val/Val genotypes were associated with an increased risk of MS in all study subjects and Caucasians (OR = 2.28, 95% CI: 1.68-3.10, P-z < 0.001 and OR = 2.30, 95% CI: 1.66-3.20, P-z < 0.001, respectively). Sensitivity analysis showed that no individual study was found to be significantly biasing the pooled results. Although meta-analysis also suggested an association between the CD24 Val/Val genotypes and SLE risk in Caucasians (OR = 1.71, 95% CI: 1.31-2.24, P-z < 0.001), sensitivity analysis demonstrated that the association was not statistically significant after removing a Spanish study. In conclusion, this meta-analysis suggests that the CD24 Ala57Val polymorphism is associated with an increased risk of MS in Caucasians. However, the available evidence is not sufficient to support an association between the CD24 Ala57Val polymorphism and SLE risk.