Possible association between multiple sclerosis and the human T cell leukemia virus (HTLV)-related endogenous element, HRES-1.

In the present study we searched for an association between the human endogenous retroviral element HRES-1 and multiple sclerosis (MS). Fragments of this endogenous retrovirus were amplified for subsequent examination by single strand conformational analysis. We did not find HRES-1 markers exclusively linked with MS and only the two already known polymorphisms, which define three alleles of HRES-1, were detected. However, we found a significant difference in the distribution of these alleles between a group of 87 MS patients and a control group of 158 healthy individuals (P = 0.014). There were no differences in the distribution of the HRES-1 allelic forms between MS patients with a relapsing-remitting course and patients with chronic progressive MS. Our results provide evidence of an association between HRES-1 and MS. Possible explanations for this are discussed.