Calpain 10 and type 2 diabetes

In the first successful genome-wide scan of a complex disease like type 2 diabetes, Graeme Bell and co-workers reported significant linkage (LOD 4.1; p < 10-4) between type 2 diabetes in Mexican American sib pairs and a locus on chromosome 2q37, called NIDDM1 (Hanis et al. 1996). Still, this region was quite large (12 cM), encompassing a large number of putative genes. A re-examination of the data suggested an interaction (epistasis) with another locus on chromosome 15 (with a nominal LOD of 1.5). This enabled the researchers to narrow the region down to 7cM. Luckily, because it is telomeric with a high recombination rate, the 7cM genetic map only represents 1.7 megabases of physical DNA. To clone the underlying gene, they genotyped 21 SNPs in this 7 cM interval and identified a three-marker haplotype that was nominally associated with type 2 diabetes. At the end, three intronic SNPs (43,44 and 63) in the gene encoding for calpain 10 (CAPN10) could explain most of the linkage (Horikawa et al. 2000). Calpain 10, a cystein protease with largely unknown functions in glucose metabolism, was not an obvious candidate gene for type 2 diabetes. Despite a number of subsequent negative studies, several meta-analyses have shown consistent association of SNPs 43 and 44 with type 2 diabetes (Parikh & Groop 2004). Neither was it easy to understand how intronic variation in this gene could increase risk for type 2 diabetes. Carriers of the G allele of SNP43 are associated with decreased expression of the gene in skeletal muscle and insulin resistance. How this translates into increased risk of type 2 diabetes is not known and will require functional studies.

Supplements For Diabetics

Supplements For Diabetics

All you need is a proper diet of fresh fruits and vegetables and get plenty of exercise and you'll be fine. Ever heard those words from your doctor? If that's all heshe recommends then you're missing out an important ingredient for health that he's not telling you. Fact is that you can adhere to the strictest diet, watch everything you eat and get the exercise of amarathon runner and still come down with diabetic complications. Diet, exercise and standard drug treatments simply aren't enough to help keep your diabetes under control.

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