|Genome scans for type 2 diabetes confirm potential hotspot|
Edward R. Winstead
August 20, 2001
Many genes are likely to contribute to type 2 diabetes, and one of these may reside on human chromosome 1, according to a new study by British researchers. The same region of chromosome 1 has been implicated in previous studies involving U.S., French, and Native American families. The new finding is based on genome scans of British families that have two or more members affected by type 2 diabetes.
"The results of this genome scan of 573 pedigrees provide further confirmation that no single locus plays a major role in type 2 diabetes susceptibility," the researchers write in The American Journal of Human Genetics. The data support the hypothesis that type 2 diabetes involves environmental factors and a number of genes that, on their own, are modest risk factors.
Mark I. McCarthy, of the Imperial College Genetics and Genomics Research Institute in the U.K., led the study, which is the fourth to report a potential susceptibility locus on chromosome 1. The first was in 1998, when researchers detected linkage to the chromosome among Pima Indian families. The chromosome was implicated the following year in scans of Utah families, and again in 2000 in a study of French families.
Although the boundaries of the regions reported in each study differ somewhat, it is plausible that they are indicating the same locus, the researchers say. The evidence is "entirely consistent with detection of a common susceptibility locus in the different studies," they write.
Further support for the importance of the chromosome 1 region comes from analyses of an animal model of type 2 diabetes. Genome scans of the Goto-Kakizaki rat revealed a susceptibility locus on the region of rat chromosome 2 that corresponds to human chromosome 1.
. . .