Molecular genetic analysis of the human sorbitol dehydrogenase gene

The polyol pathway comprises the enzymes aldose reductase and sorbitol dehydrogenase, which convert glucose to sorbitol and sorbitol to fructose, respectively, particularly in hyperglycemic states. The accumulation and toxicity of sorbitol in specific tissues has been implicated in the development of microvascular problems in some diabetic patients. Inappropriate sorbitol accumulation in some patients may be the result of polymorphic variation in the human sorbitol dehydrogenase gene, causing reduced expression levels or enzymatic activity. We now describe the structure and expression profile of the human sorbitol dehydrogenase gene and identify a range of polymorphic variants that may be useful for co-segregation studies in diabetic patients with and without severe clinical complications from their disease.