Mutations in mitochondrial control region DNA in gastric tumours of Japanese patients.
The non-coding control region of mitochondrial DNA (mtDNA), containing the hypervariable regions HV1 and HV2 and the D-loop region, was screened for mutations in 45 gastric tumours (15 tumours each of adenoma, differentiated adenocarcinoma and undifferentiated carcinoma). We found mutations in two of the 45 tumours (4%); a 1 bp A deletion at nucleotide position 248 in a differentiated adenocarcinoma and a G to A transition at nucleotide position 16,129 in an adenoma. We also observed 10 polymorphisms, four of which were not previously recorded. Both mtDNA mutations were present in replication error negative (RER-) tumours. Short mono- or dinucleotide repeats in the control region, such as (C)7, (A)5 or (CA)5, were not altered regardless of nuclear genetic instability. In summary, mtDNA is mutated in a subset of benign and malignant gastric tumours, but, disruption of the mtDNA repair system appears not to be significantly involved in gastric tumours of Japanese patients.
Tamura
G
G
Department of Pathology, Yamagata University School of Medicine, Japan. gtamura@med.id.yamagata-u.ac.jp
Nishizuka
S
S
Maesawa
C
C
Suzuki
Y
Y
Iwaya
T
T
Sakata
K
K
Endoh
Y
Y
Motoyama
T
T
D004260:DNA Repair; D004272:DNA, Mitochondrial / Q000235:genetics*; D004273:DNA, Neoplasm / Q000235:genetics*; D006801:Humans; D007564:Japan; D019901:Locus Control Region; D009154:Mutation / Q000235:genetics*; D016133:Polymerase Chain Reaction / Q000379:methods; D011110:Polymorphism, Genetic; D013274:Stomach Neoplasms / Q000235:genetics*
D004272:DNA, Mitochondrial; D004273:DNA, Neoplasm