A previous study on females with RA found that HLA-DRB1*03/DRB1*03 was associated with the development of RA, while HLA-DRB1*13/DRB1*03 represents a protective effect (38), other studies found that the haplotype HLA-DQB1*3 was linked to HLA-DRB1*09:01 or *04 and the haplotype HLA-DQB*05 linked to HLA-DRB1*01:01, *01:02, *01:03, and *10:01, and they were positively associated with RA in Caucasians (34). Here, HLA-DRB1 is linked to rheumatoid arthritis.