Human sample from Brain Supracellar region
Homo sapiens
Isocitrate dehydrogenase one and two genes are homologous metabolic isozymes, and mutation of these genes generates a neomorphic enzyme, which can lead to the abnormal accumulation of two hydroxyglutarate and promotes tumorigenesis. IDH1 mutation is an early event in brain tumorigenesis, over 70 percent of grade two and grade three gliomas have mutation in IDH genes. The molecular detection of IDH1 and IDH2 mutations has become standard practice in many institutions, and has proven useful in the clinical management of gliomas. We have sequenced by capillary method brain tumor samples for IDH2 mutations. In a case of Yemeni patient with adamantinomatous craniopharyngioma a novel missense mutation in IDH2 codon 472C to T; amino acid changed Pro158Ser was detected by capillary sequencing. This novel mutation was not reported in CNS tumors so far. However, this variant was reported in a case of pancreatic ductal adenocarcinoma only so far. The brain tissue samples were collected, and the DNA extraction was performed using kit from Qiagen. Investigation of mutations in exon 4 IDH2 were done as reported previously by using primers to flank variants in this gene. For IDH2, a 288 base pairs sequence with the entire exon 4 was amplified using forward primer within intron 3 and a reverse primer within intron 4. For PCR genomic DNA was amplified, and this products were purified using Agencourt Ampure magnetic beads kit. PCR product was used in Sequencing PCR Big Dye reaction. Big Dye reaction products were purified, then the sequencing was done on ABI 3500 Genetic Analyzer. References. Patel KP, Barkoh BA, Chen Z, others. Journal of Molecular Diagnostics. 2011, 13, 678. van den Bent MJ, Dubbink HJ, Marie Y, others. Clinical Cancer Research. 2010, 16, 1597. Wartenberg M, Cibin S, Zlobec I, others. Clinical Cancer Research. 2018, 24, 1. Yan H, Parsons DW, Jin G, others. New England Journal of Medicine. 2009, 360, 765.