A gene mapping between the S and D regions of the H-2 complex influences resistance to Trichinella spiralis infections of mice.

The strains B10.S(7R), B10.S(23R) and B10.S(24R), all thought to be genetically identical, differ in levels of susceptibility to infection with Trichinella spiralis. In a series of nine independent experiments, B10.S(7R) was shown to be more susceptible than the other two strains. In another series of seven experiments, the strain B10.A(18R) was shown to be more susceptible to infection with T. spiralis than the strains B10.S(21R) or B10.BAR-5, all of which were thought to share common H-2 alleles. These results indicate that a gene mapping between the S and D loci influences susceptibility to infection with T. spiralis. Typing of these strains for Qa and Tl loci rule out the possibility of a double crossover accounting for the differences observed. The new gene is designated Ts-2. Previously published data have also been reinterpreted and another gene Ts-1 is shown to be associated with The A beta locus. When the d allele is expressed at the Ts-2 locus, strains of mice expressing s, q, f or b alleles at Ts-1 are rendered more susceptible to infection.