ev 22, a new endogenous avian leukosis virus locus found in chickens with spontaneous autoimmune thyroiditis.

Chickens of the Obese strain (OS) develop a hereditary spontaneous autoimmune thyroiditis (SAT) which closely resembles human Hashimoto's disease. Analysis of the endogenous viruses harboured by these animals revealed a new endogenous virus (ev22) detected as a 5.5 kb Sac I fragment. Crossbreeding experiments showed that ev22 is vertically transmitted as an autosomal trait not associated with major histocompatibility (MHC) alleles. Preliminary experiments indicate that ev22 does not necessarily cause SAT, however, it may have a modulatory role in the development of the disease.