Impact of Animal Strain on Gene Expression in a Rat Model of Acute Cardiac Rejection

The expression levels of many genes show wide natural variation among strains or populations. This study investigated the potential for animal strain-related genotypic differences to confound gene expression profiles in acute cellular rejection (ACR). Additional analysis allowed for selection of 49 candidate genes uniquely associated with ACR, but only after accounting for the unexpectedly large effect of animal strain. Studies of ACR that examine gene expression in peripheral blood may be confounded by strain differences. These results indicate the need for study designs that eliminate or control for the large effect of genetic background on the transcriptome of immune cells.