Genetic analysis of susceptibility to Theiler's murine encephalomyelitis virus-induced demyelinating disease in the SWR strain.

SWR/J mice are susceptible to immune-mediated central (CNS) demyelination following infection by Theiler's murine encephalomyelitis virus (TMEV). SWR/J susceptibility is genetically dominant, when outcrossed to resistant H-2b strains. Non-H-2 differences between C57BL/6 and C57L/J (both H-2b) alter effects of 'susceptibility' genes, especially H-2q, from SWR/J. Genetic analysis of differential susceptibility to demyelination between SWR/J and C57L/J indicates that one copy of H-2q is sufficient for disease, and that SWR/J mice carry a non-H-2 gene which can lead to disease in the absence of H-2q. Differential susceptibility between SWR/J and C57BL/6 is determined by a single non-H-2 locus, which may or may not be the same as that differing between SWR/J and C57L/J.