For quite some time, many researchers and lay people alike have subscribed to what is known as the "Thrifty Genotype Theory." Basically, this theory suggests that cycles of feast and famine that occurred early in human history created a gene that assists the body in utilizing scarce nutrients.

Because we as humans no longer operate on a feast or famine eating cycle, however, this gene -- which still remains -- leads to obesity and diabetes. In addition, this theory pointed to certain ethnic groups; Native Americans, Mexican Americans, African Americans, Australian Aborigine and other indigenous groups as being genetically prone to diabetes because of their link to this particular gene.

In efforts to challenge the ethnic presumptions, and erode the "Thrifty Genotype Theory" altogether, a study by U.S. and Australian researchers examines existing genetic studies published across a variety of disciplines. Whereas past studies into the genetic link to diabetes failed to control for outside variables, this new study factors in poverty, housing segregation and poor diet -- and, upon completion of the researchers' analysis, all were found to be stronger indicators of diabetes than genes.

Research conducted by an anthropology professor at the University of California Irvine calls into question the imperfect science behind labeling ethnic groups for classifying and studying chronic illness. Paying specific attention to the problematic nature of linking health inequalities and so-called predisposition to genetic variation rather than social factors such as poverty and access to adequate health care, the research raises questions about the established, inexact methods of establishing race and ethnicity.

After following the trail of DNA samples from when they were first donated by people living along the US-Mexican border, to the eventual publication of findings based on these samples in scientific journal, the researchers found that the resulting data utilized by U.S. and British scientists used social and historical explanations -- not biological differences -- to define race and ethnicity for their research. Arbitrary labeling systems such as these, and their attendant genetic studies, are behind data suggesting that certain ethnic groups are predisposed to chronic illnesses like diabetes. In fact, this very thing was suggested of Mexican Americans, sparking international debate.

The researchers fear that the current methods of labeling race for research purposes will produce dissimilar and inconclusive results from study to study. This could effect the way a disease such is diabetes is treated for any given race, as it may be viewed as a genetically predisposed problem, for example, when in reality the problem is rooted more in social inequity.