Background
The Major Histocompatibility Complex (MHC) has been consistently associated with susceptibility to MS and the course of several other human AutoImmune Diseases.
A putative association between the course and severity of MS and the MHC remains controversial.
Methods
DR and DQ genotyping by either restriction fragment length PolyMorphism or sequence-specific PCR-based typing in 119 patients.
Representing 73.4% of the population with MS evaluated in a cross-sectional disability survey and 100 healthy controls from Olmsted County, Minnesota.
Results
We found a positive association between MS susceptibility and the DR15-DQ6 and DR13-DQ7 haplotypes, and we found a negative association with the DR1-DQ5 haplotype.
We found a trend to a positive association of Primary/Progressive MS with DR4-DQ8 and DR1-DQ5 and an association of "Bout Onset" MS with DR17-DQ2.
We did not find an association with disease severity, as defined by EDSS/duration.
Conclusion
Lack of consistency between different studies may be due to regional variation in MS and limitations of power but likely indicate a minor effect of MHC Class II Genes on the course and severity of MS.