Abstract

Infectious disease agents have a profound effect on human biological and cultural evolution. Understanding the processes involved in the biological response to pathogens and the genetic factors that contribute to disease resistance and susceptibility, are integral to understanding the adaptation to diseases by New World Aboriginal populations. Complex historic and evolutionary events led to the immunogenetic profile of the North American indigenous population, and it is only within an evolutionary context that we can make sense of the differential rates of morbidity and mortality that occurred and continue to occur between ethnic groups. This research compared the frequency of single nucleotide polymorphisms (SNPs) in the promoter region of cytokine proteins (key regulators of the immune system) in a contemporary Aboriginal and Caucasian study population and established that a significant difference exists. Results suggest that the contemporary Aboriginal study population differs from Caucasians in their ability to express cytokines that are effective against infectious pathogens that require a cell-mediated immune response. The analysis of the cytokine SNP frequencies maintained by the contemporary Aboriginal population within a functional, adaptive context suggests substantially more complex pattern of evolution.

To explore the observed immunogenetic profile of Aboriginals within an evolutionary framework, a novel technique for detecting SNPs in the cytokine promoter regions of ancient human remains from Manitoba was developed. The development of new molecular methods for detecting SNPs which have been shown to be linked to disease resistance and susceptibility, is the first step towards understanding the role of genetic factors in the human immune response to infectious disease. This will contribute to understanding why certain infectious diseases continue to profoundly impact contemporary North American Aboriginal populations.