HLA-A, B, C, DR, MT, and MB antigens in recurrent aphthous stomatitis.

In this report we have investigated the frequencies of HLA-A, B, C, DR, MT, and MB markers in 26 Sicilian subjects affected by recurrent aphthous stomatitis (RAS) and in 84 healthy controls. Our data show that the frequency of HLA-DR7 antigen is significantly increased in RAS-affected persons (61.5% versus 21.4%; pc less than 0.0025), whereas the B5 antigen frequency is decreased significantly (absent in patients versus 27.3% in controls; pc = 0.04). Thus, present results suggest that HLA-linked genetic factors may play a role in the development of RAS.