DRB1*04:05-positive MS patients had lower MSSS scores and lower frequencies of Barkhof brain lesions and CSF IgG abnormalities than DRB1*04:05-negative MS patients (p = 0.0415, p = 0.0026, and p < 0.0001, respectively).
Barkhof brain lesion-negative (-) patients had a markedly lower frequency of HLA-DRB1*0901 than controls (P(corr) < 0.05), whereas the frequency of DRB1*1501 was increased in the Barkhof brain lesion-positive (+) group, although this increase was not significant after correction.
Conversion to MS was positively associated with the DRB1*1501.DQA1*0102.DQB1*0602 haplotype, but the influence of HLA was only significant in patients with disseminated brain lesions at presentation (MRI positive); MS developed in 86% of MRI-positive, DRB1*1501-positive patients compared with 55% of MRI-positive, DRB1*1501-negative patients (p < 0.025).