HLA-I Alleles Are Associated With Genetic Susceptibility To Vitiligo In Chinese Hans

Background Vitiligo is an acquired depigmentary disorder of the skin that affects about 0.5-1% of the world population.The studies showed that genetic factor has been suggested as playing etiological role in the disease. Attentions have been focused on possible genetic determinants. Genome-wide linkage analyses have identified putative susceptibility loci on chromosome lp, 6p. Recently, the study has mapped a major locus for vitiligo at chromosome 6p21.3. During the past years, HLA- A2, A3 A10 A30+31, B13, B15 antigens and DRB1 *070x and-DRB 1 * 1201,2 allelics have been reported to increase the frequencies in patients with vitiligo in Chinese. The introduction of polymerase chain reaction with sequence-specific primers (PCR-SSP) has proved to be sensitive and specific in detecting HLA-I alleles. Objective To explore HLA-I alleles that may be involved in the genetic susceptibility to vitiligo. Method We determined the distributions of HLA-I allelic frequencies by using polymerase chain reaction with sequence-specific primers (PCR-SSP) in 187 Han Chinese patients with vitiligo and 204 healthy controls. Results The Results as follows: (1) The frequencies of HLA-A*2501 (10.69% vs 3.43%, OR=3.69, Pc=0.00054), -A*30 (6.95% vs 1.47%, OR=5.33, Pc=0.00149), -B*13 (21.39% vs 13.73%, OR=1.98, Pc =0.038), -B*27 (10.43% vs 4.90%, OR=2.42, Pc=0.0456) and -Cw*0602 (14.17% vs 5.15%, OR=3.45, Pc=0.000157) significantly increased in the patients, while the frequency of HLA-A*66 (1.93% vs 9.69%, OR=0.17, Pc=0.000078) decreased, when compared with the controls. (2) HLA-A*2501(17.64% vs 3.43%, OR=7.34, Pc<10-7), -A*30(8.02% vs 1.47%, OR=16.64, Pc=0.00113), -B*13(27.12% vs 13.73%, OR=3.13, Pc =0.00026), -B*27(14.36% vs 4.90%, OR=3.71, Pc=0.00123)and -Cw*0602(20.22% vs 5.15%, OR=5.91, Pc<10-7) significantly increased in the generalized vitiligo and HLA-A*30(6.25%vsl.47%,OR=4.43, Pc=0.045) significantly increased in the localized vitiligo. (3) HLA-A*2501(14.71% vs 3.43%, OR=5.65, Pc=0.00016),-A*30(17.65%vsl.47%, OR=17.82, Pc<10"6), -B*13(26.47% vs 13.73%, OR=2.97, Pc=0.0171), -B*27 (13.73%vs4.90%, OR=3.48, Pc=0.038) and -Cw*0602 (24.50% vs 5.15%, OR=7.82, Pc<10'7) significantly increased in the childhood vitiligo and HLA-A*2501(9.50%vs3.43%, OR=3.11, Pc=0.018) significantly increased in the adult vitiligo.Conclusion (1) HLA-A*2501, -A*30, -B*13, -B*27 and-Cw*0602 alleles may be the susceptible genes or they may have close linkage with the susceptible genes to vitiligo. HLA-A*66 allele has procetive effect against the development of vitiligo in Chinese. (2) There may be a different genetic background among different phenotypes of vitiligo in Han Chinese.