Mutational analysis of whole mitochondrial DNA in patients with MELAS and MERRF diseases.

Abstract

Mitochondrial diseases are clinically and genetically heterogeneous disorders, which make the exact diagnosis and classification difficult. The purpose of this study was to identify pathogenic mtDNA mutations in 61 Korean unrelated families (or isolated patients) with MELAS or MERRF. In particular, the mtDNA sequences were completely determined for 49 patients. From the mutational analysis of mtDNA obtained from blood, 5 confirmed pathogenic mutations were identified in 17 families, and 4 unreported pathogenically suspected mutations were identified in 4 families. The m.3243A>G in the tRNA(Leu(UUR))was predominantly observed in 10 MELAS families, and followed by m.8344A>G in the tRNA(Lys) of 4 MERRF families. Most pathogenic mutations showed heteroplasmy, and the rates were considerably different within the familial members. Patients with a higher rate of mutations showed a tendency of having more severe clinical phenotypes, but not in all cases. This study will be helpful for the molecular diagnosis of mitochondrial diseases, as well as establishment of mtDNA database in Koreans.

• Authors: Byung-Ok Choi, Jung Hee Hwang, Eun Min Cho, Eun Hye Jeong, Young Se Hyun, Hyeon Jeong Jeon, Ki Min Seong, Nam Soo Cho, Ki Wha Chung
• Journal: Experimental & molecular medicine (Exp Mol Med) Vol. 42 Issue 6 Pg. 446-55 (Jun 30 2010) ISSN: 2092-6413 [Electronic] United States
• PMID: 20440095 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• DNA, Mitochondrial

Topics

• Adolescent
• Adult
• Amino Acid Sequence
• Asian People (genetics)
• Base Sequence
• DNA Mutational Analysis
• DNA, Mitochondrial (analysis, genetics)
• Female
• Humans
• MELAS Syndrome (diagnosis, genetics)
• MERRF Syndrome (diagnosis, genetics)
• Male
• Middle Aged
• Molecular Diagnostic Techniques
• Pedigree
• Polymorphism, Single Nucleotide
• Sequence Homology
• Young Adult