HLA class II genotypes in Mexican Mestizos with familial sand nonfamilial multiple sclerosis

Predisposition to MS is associated with the HLA-DR2 antigen in white patien ts. The authors investigated the genetic factors behind the increasing freq uency of MS in the Mexican population. HLA-DR and DQ were analyzed in 17 pa tients with MS, 15 of their first-degree relatives, and 99 healthy ethnical ly matched controls. DR2 or DR3 was found in 15 of 17 patients. In controls , both alleles had frequencies less than 0.05. MS in Mexican patients was a ssociated with HLA-DR2 and DR3.