Mitochondrial diabetes mellitus.

In the last few years, several mitochondrial DNA mutations and deletions have been described in association with various human diseases. Mitochondrial disorders, though long regarded strictly as neuromuscular diseases, may in fact involve non-neuromuscular symptoms. Diabetes mellitus has been reported in patients presenting with large mtDNA rearrangements (deletion, deletion-duplication) or in association with mtDNA point mutations, generally in tRNA genes (tRNA(Leu(UUR)). Genetic studies have shown that these disorders occur in sporadic cases or can be maternally inherited. The main clinical feature of mitochondrial diabetes is its nearly-consistent association with other symptoms (deafness, neurologic disorders, cardiac failure, renal failure, etc.). This paper provides a review of different types of mtDNA abnormalities associated with diabetes and a study of the prevalence of mitochondrial diabetes mellitus.