Loss of heteroplasmy in the displacement loop of brain mitochondrial DNA in astrocytic tumors.
The aim of this study was the determination of D-loop heteroplasmy in astrocytic brain tumors. DNA fragments corresponding to the hypervariable region 2 of the mitochondrial displacement loop (D-loop) from 12 astrocytic tumors and 2 corresponding brain samples were cloned into a plasmid vector. Heteroduplex analysis revealed high sequence variability in the brain samples and a subfraction of grade 2 and grade 3 tumors. Furthermore, the results were suggestive of a very low degree of heteroplasmy in all glioblastomas. This was confirmed by direct sequencing of 223 cloned DNA samples from nine individuals. Heteroplasmy was caused in most cases by a well-known length polymorphism of a homopolymeric c-tract. Heteroplasmy of the two reference brain samples was lost in the corresponding tumors. Genes Chromosomes Cancer 26:80-83, 1999.
Kirches
E
E
Institut für Neuropathologie, Otto von Guericke Universität Magdeburg, Magdeburg, Germany.
Michael
M
M
Woy
C
C
Schneider
T
T
Warich-Kirches
M
M
Schneider-Stock
R
R
Winkler
K
K
Wittig
H
H
Dietzmann
K
K
D000328:Adult; D000368:Aged; D001254:Astrocytoma / Q000235:genetics*; D001932:Brain Neoplasms / Q000235:genetics*; D002648:Child; D004272:DNA, Mitochondrial / Q000737:chemistry / Q000235:genetics*; D005260:Female; D014644:Genetic Variation; D005909:Glioblastoma / Q000235:genetics; D020180:Heteroduplex Analysis; D006801:Humans; D008297:Male; D008875:Middle Aged; D009690:Nucleic Acid Conformation
D004272:DNA, Mitochondrial