Single locus in BXH-2 mice responsible for inability to control early proliferation of Trypanosoma cruzi.

The inability of the BXH-2 recombinant inbred strain to limit proliferation of Trypanosoma cruzi during the first 2 weeks after infection was found to be controlled by a single locus difference between the BXH-2 strain and each of its parental strains: C3H/HeJ and C57BL/6J. In both cases, the inability to limit parasite proliferation acted like a recessive trait. The loci in the C3H and C57BL/6 strains appear to be identical since all F2 mice derived from these strains displayed the early control trait. A mutation is thus likely to have occurred in the derivation of the BXH-2 strain. The provisional designation Crz has been given to the locus in the BXH-2 strain that is responsible for its failure to control early proliferation of T. cruzi. The Crz locus is distinct from the lpr gene which has also been associated with increased levels of parasitemia early in the course of the infection.