Send to

Choose Destination
Int J Cancer. 1999 Nov 26;83(5):625-9.

Mitochondrial gene mutation, but not large-scale deletion, is a feature of colorectal carcinomas with mitochondrial microsatellite instability.

Author information

Division of Pathology, Central Clinical Laboratory, School of Medicine, Iwate Medical University, Morioka City, Japan.


We have shown that microsatellite instability (MSI) occurs in mitochondrial DNA (mtDNA) of colorectal carcinomas. To determine whether such mitochondrial microsatellite instability (mtMSI) is associated with certain forms of mitochondrial gene alterations, we extended the screening in the same series of 45 carcinomas. Analysis by whole mtDNA amplification (16.5 kb) and digestion revealed no detectable large-scale change in these carcinomas. In contrast, single-strand conformation polymorphism (SSCP) analysis demonstrated NADH dehydrogense (ND) gene alterations in 7 carcinomas (16%), including 3 mononucleotide repeat alterations, 2 missense mutations and 1 small (15 bp) deletion. Six of these 7 carcinomas also exhibited mtMSI of the (C)n sequence in the displacement-loop (D-loop) region. Thus, frameshift or missense mutations rather than large-scale changes in the mtDNA were more common features in colorectal carcinomas with mtMSI. By analogy to mutational features of nuclear MSI, mtMSI most likely results from certain repair deficiencies in the mtDNA and probably plays a role in the tumor development of certain colorectal carcinomas.

[Indexed for MEDLINE]
Free full text

Supplemental Content

Full text links

Icon for Wiley
Loading ...
Support Center