Maternally transmitted partial direct tandem duplication of mitochondrial DNA associated with diabetes mellitus

• Published in: Human molecular genetics 1993-10, Vol.2 (10), p.1619-1624
• Main Authors: Dunbar, D.R., Moonie, P.A., Swingler, R.J., Davidson, D., Roberts, R., Holt, I.J.
• Format: Article
• Language: English
• Subjects: Adult; Amino Acid Sequence; Base Sequence; Biological and medical sciences; Diabetes Complications; diabetes mellitus; Diabetes Mellitus - genetics; Diabetes. Impaired glucose tolerance; DNA; DNA Mutational Analysis; DNA, Mitochondrial - genetics; duplication; Endocrine pancreas. Apud cells (diseases); Endocrinopathies; Etiopathogenesis. Screening. Investigations. Target tissue resistance; Extrachromosomal Inheritance; Humans; Male; man; Medical sciences; mitochondria; Mitochondrial Myopathies - complications; Mitochondrial Myopathies - genetics; Mitochondrial Myopathies - pathology; Molecular Sequence Data; Multigene Family; Muscles - pathology; Sequence Deletion; transmission
• ISSN: 0964-6906; 1460-2083
• DOI: 10.1093/hmg/2.10.1619

Mitochondrial DNA from a 38 year old male with diabetes mellitus and features of mitochondrial dysfunction was analysed and shown to include a population with a partial duplication. The partially duplicated mitochondrial DNA molecules were evident in both muscle and blood. The region of mitochondrial DNA duplicated includes the origin of heavy strand replication, but not the light strand origin. This patient has features In common with other cases of partial direct tandem duplications and with a family which was reported to harbour a 10.4 kb mtDNA deletion. Initial restriction enzyme analysis of our case produced results consistent with a partial deletion of mitochondrial DNA. This leads us to propose that the rarity of reports of partial mitochondrial DNA duplications may stem in part from the classification of such mutants as partial deletions.