Comparison of Anti-IFN-β Reactivities for HLA-DRB1 Alleles in the Study and Validation Groups A significant increase of ELISA reactivities was measured for HLA-DRB1∗0401 and HLA-DRB1∗0408 alleles (p value ≤ 0.01). DRB1∗0402, DRB1∗0403, and DRB1∗0404 seem to have a protective effect.