A variant of CLEC16A gene confers protection for Vogt-Koyanagi-Harada syndrome but not for Behcet's disease in a Chinese Han population

Vogt-Koyanagi-Harada (VKH) syndrome and Behcet's disease (BD) are two common form of uveitis in China. The aim of this study was to investigate the association of C-type lectin domain family 16, member A (CLEC16A) gene polymorphisms with Vogt-Koyanagi-Harada syndrome and Behcet's disease in a Chinese Han population. A two-stage association study was carried out in 988 VKH syndrome patients, 400 BD patients and 976 healthy controls. Eight single nucleotide polymorphisms of CLEC16A gene were determined with the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. The data were analyzed by chi(2) test or Fisher's exact test and corrected for multiple comparisons by the Bonferroni method. The first stage study showed that the frequency of the A allele of rs6498169 was significantly decreased in VKH syndrome patients (Pc = 1.1 x 10(-2), OR = 0.7, 95%Cl = 0.6-0.9). No significant association was observed in the other 7 SNPs between VKH syndrome patients and controls. No association was found with BD for the 8 SNPs tested. We further confirmed the association of single nucleotide polymorphism rs6498169 with VKH syndrome in another cohort. Consistent with the first stage study, the combined study showed significantly lower frequencies of the AA genotype and the A allele of rs6498169 in VKH syndrome patients (Pc = 3.5 x 10(-4), OR = 0.6, 95XCI = 0.5-0.7; Pc = 8.2 x 10(-4), OR = 0.8, 95%CI = 0.7-0.9, respectively). In conclusion, the study suggested that a CLEC16A polymorphism may be protective against VKH syndrome in a Chinese Han population.