Production of murine leukemia virus in the immunodeficient wasted mutant mouse is associated with the wst allele.

The recessive mutation "wasted" (wst) is responsible for a neuroimmunological syndrome and premature death in homozygous wst/wst mice. In contrast, +/wst heterozygotes appear phenotypically normal. The present study assessed the production of endogenous murine leukemia virus (MuLV) in lymphoid organs of homozygous wasted (wst/wst), heterozygous wasted (+/wst) and control wild type (+/+) mice. Neither mutant nor control mice produced ecotropic MuLV. In contrast, lymphoid organs from wst/wst and +/wst mice produced endogenous xenotropic MuLV. MuLV production was not detectable in the same organs of +/+ control mice. +/wst heterozygotes produced xenotropic MuLV in the thymus, spleen and mesenteric lymph nodes but not in the bone marrow. Wst/wst mutants produced xenotropic MuLV, but only in the thymus. These findings demonstrate an association between the production of endogenous xenotropic MuLV and the wasted mutation.