Open AccessIDH1 Mutations in Oligodendroglial Tumors: Comparative Analysis of Direct Sequencing, Pyrosequencing, Immunohistochemistry, Nested PCR and PNA ‐Mediated Clamping PCR
Author(s) -
Lee Dakeun,
Suh YeonLim,
Kang So Young,
Park TaeIn,
Jeong Ji Yun,
Kim SeHoon
Publication year - 2013
Publication title -
brain pathology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.986
H-Index - 132
eISSN - 1750-3639
pISSN - 1015-6305
DOI - 10.1111/bpa.12000
Subject(s) - idh1 , microbiology and biotechnology , biology , pyrosequencing , immunohistochemistry , mutant , polymerase chain reaction , mutation , isocitrate dehydrogenase , dna sequencing , cold pcr , dna , gene , point mutation , genetics , biochemistry , enzyme , immunology
Mutations in isocitrate dehydrogenase 1 ( IDH1 ) are found in a high proportion of glial tumors and have a significant prognostic impact. Although direct sequencing has been considered to be the gold‐standard method to detect this mutation, the sensitivity of this technique has been questioned especially because specimens from glial tumors may contain large numbers of non‐tumor cells. We screened 141 cases of oligodendroglial tumors for IDH1 mutations using peptide nucleic acid ( PNA )‐mediated clamping polymerase chain reaction ( PCR ) and compared the results with the results of direct sequencing, pyrosequencing, and immunohistochemistry ( IHC ). Nested PCR was only performed in cases having mutant IDH1 only discovered by clamping PCR . Using dilution experiments mixing IDH1 wild‐type and mutant DNA samples, clamping PCR detected mutations in samples with a 1% tumor DNA composition. Using PNA clamping PCR , we detected 138 of 141 (97.9%) cases with mutant IDH1 in our series, which is significantly higher ( P = 0.016; PNA clamping vs. direct sequencing) than those of direct sequencing (74.5%), pyrosequencing (75.2%) and IHC (75.9%). From our results, almost all oligodendroglial tumors have IDH1 mutations, and this suggests that IDH1 mutation is an early and common event especially in the development of oligodendroglial tumors.