These results confirm the proposed positive association of the Dw2 (DRB1*1501 DQA1*0102 DQB1*0602) haplotype with MS in Caucasians in our Turkish population (25 vs. 8, p = 0.003, OR = 3.7).
This observation supports the hypothesis that "normal" genes, common to all carriers of the DR15,DQ6,Dw2 haplotype, confer the increased genetic susceptibility to MS associated with this haplotype.
We used an extremes-of-outcome design with 48 benign and 20 malignant MS patients to assess whether or not DNA methylation at HLA-DRB1*1501 and/or HLA-DRB5 also contributes to MS phenotypic heterogeneity.