Abstract

Type 2 diabetes (T2D) is a complex human disease which has become extremely prevalent among indigenous populations of Canada and the United States in recent decades. T2D is etiologically complex and refers to a group of disparate metabolic diseases, having major genetic and environmental risk factors. It is believed that a combination of genetic susceptibility and lifestyle changes among indigenous people are to blame for the recent diabetes epidemic. Hypotheses for possible thrifty genotypes and phenotypes have been proposed to explain the causes of the high incidence of T2D in North American Aboriginal populations. Non-genetic factors such as income, living conditions and crime rates also show evidence of affecting T2D risk among Aboriginal people through physiological stress mechanisms. Recent advances in genetic technology have facilitated the identification of a number of gene variants that show positive predictive and diagnostic value for T2D. One of these genes is specific to a group of Aboriginal people in Canada and its occurrence is consistent with the thrifty genotype hypothesis. Identification of susceptibility genes can provide researchers with a starting point for understanding the specific metabolic processes responsible for causing T2D in different populations. This information can be used for producing methods of therapeutic intervention in the future. In the meantime, reducing environmental risk factors for T2D through lifestyle changes remain an important means of preventing the expression of the disease phenotype in Native American and Canadian Aboriginal people.

Key words: Type 2 diabetes, Aboriginals, North America, genetic and non-genetic factors