Congenic mice for the identification of genes responding to infection with Trypanosoma congolense

Abstract

AJ, Balb/c and C57BL/6 mice differ in response to infection with Trypanosoma congolense with mean survival times of 15, 60 and 120 days after infection. Five QTL on chromosomes 17, 5, and 1 have been identified that are involved in the control of this phenotype. We have constructed three congenic mouse lines with the most resistant C57BL/6 alleles introgressed into the most susceptible AJ background. The congenic mice have been phenotyped and for each line the difference in survival time between congenic mice and litter mate controls is not significantly different from the difference in survival attributed to the corresponding QTL. The mice have been genotyped with 800 informative SNP from the Illumina murine SNP mapping set to identify residual regions of C57BL/6 DNA that have not been eliminated by backcrossing. The expression of all liver genes has been determined on Affymetrix and compared with the expression of genes from inbred parental AJ mice. A number of genes that have AJ genotypes were found to be differentially expressed relative to AJ inbred controls suggesting that these genes are trans regulated by genes in the QTL.