Loss of heteroplasmy in the displacement loop of brain mitochondrial DNA in astrocytic tumors

✍ Scribed by Elmar Kirches; Matthias Michael; Cornelia Woy; Thomas Schneider; Michaela Warich-Kirches; Regine Schneider-Stock; Kirstin Winkler; Holger Wittig; Knut Dietzmann

• Publisher: John Wiley and Sons
• Year: 1999
• Tongue: English
• Weight: 69 KB
• Volume: 26
• Category: Article
• ISSN: 1045-2257
• DOI: 10.1002/(sici)1098-2264(199909)26:1<80::aid-gcc11>3.0.co;2-4

✦ Synopsis

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.