HLA-DRB1 and Parkinson disease: (ii) tag SNPs are likely to differ between populations, HLA-DRB1*0406 in JPT(Japanese in Tokyo) and HLA-DRB1*0403 in CHB(Han Chinese in Beijing) shared the same tag SNP:rs2395175, our study showed that HLA-DRB1*0403 was more common in PD patients than in controls, but the difference was no statistic significance, that partially explained why PD GWAS study in Japanese saw no evidence of HLA association even though the HLA-DRB1*0406 allele appears more frequent in Japan [20].