GENETIC SUSCEPTIBILITY TO MULTIPLE-SCLEROSIS MAY BE LINKED TO POLYMORPHISM OF THE MYELIN BASIC-PROTEIN GENE

The present paper compares the genetic polymorphism of a part of the m yelin basic protein (MBP) gene in 64 Danish MS patients with that of 5 7 normal controls. PCR analysis, using primers flanking the 5' area fr om 479 to 1812 bp upstream the initiator methionine in the MBP gene, r evealed that genetic susceptibility to MS is linked to polymorphism in the part of the MBP gene studied. Thus we found three different band patterns i.e. a homozygote with a 1445 bp long fragment, a homozygote with a fragment 1318 bp long and a heterozygote with both bands presen t. 59% of 64 patients with MS were homozygous for 1.445 kb allele, ver sus 40% of 57 control subjects, 18% of the control subjects were homoz ygous for the 1.318 kb, while only 0.7% of the MS patients possessed t his allele. The differences between incidence of the three band patter n in the MS and the control group were significant at 1% level. Valida tion analysis furthermore support, the view that the 1445 bp PCR fragm ent is associated with MS.