Compared to DQ2 serotyping of DQB1*0201 positive individuals (98%), the efficiency of DQ1 recognition is relatively low and error prone.
For this reason DQ1 serotyping is a poor method of typing for transplantation or disease association prediction or study.
DQA1*0103 (*0103) shows a negative (protective) association with many autoimmune disease, this association is apparent in Japanese studies in the *0103:DQB1*0601 haplotype, and in Europe with the *0103:DQB1*0603 haplotype, indicating the protective effect is influenced by the alpha chain of DQ.
DQA1*0103 is protective against Behçet's disease,[4][5] pemphigus vulgaris,[6] juvenile diabetes,[7][8] steroid-sensitive nephrotic syndrome,[9] myasthenia gravis[10] coeliac disease[11] multiple sclerosis,[12] chronic active hepatitis C,[13] and Vogt–Koyanagi–Harada syndrome.
[14] However, it may predispose carriers to chronic infection such as leprosy,[15] Helicobacter pylori-positive gastric lymphoma,[16] and