The HLA-DQ(alpha 1*0102, beta 1*0602) heterodimer may confer susceptibility to multiple sclerosis in the absence of the HLA-DR(alpha 1*01, beta 1*1501) heterodimer.

The frequencies of DR2, DQ6-related DRB1, DQA1, DQB1 haplotypes were compared in 181 multiple sclerosis patients and 294 controls in Norway. All individuals carried either DR2 or DQ6, i.e., the DQ(alpha 10102, beta 10602) heterodimer. The DR(alpha 101, beta 11501) and the DQ(alpha 10102, beta 10602) heterodimers were carried by 171 of the patients (94%) and 289 (98%) of the controls. Seven of the patients and one of the controls carried the DQ(alpha 10102, beta 10603) heterodimer together with the DR(alpha 101, beta 11501) heterodimer. Two patients carried the DQ(alpha 10102, beta 10602) heterodimer in the absence of the DR( alpha 101, beta 11501) heterodimer. The DR(alpha 101, beta 11501) heterodimer was not observed in the absence of the DQ(alpha 10102, beta 10602) heterodimer or the DQ(alpha 10102, beta 10603) heterodimer, neither in the patients nor in the controls. Our findings indicate that the genes encoding the DQ(alpha 10102, beta 10602) heterodimer may confer susceptibility to developing multiple sclerosis in the absence of the DRB1*1501 allele.