The higher haplotype frequency of DRB1*01:01-DQB1*05:01 and DRB1*10:01-DQB1*05:01 in the Japanese population suggests an important role of DQB1*05:01 allele in the pathogenesis of ACA positive SSc in Japanese [26]. The gene discussed is HLA-DRB1; the disease is systemic sclerosis.