Two Genes Linked to Common Types of Gliomas

Scientists have linked mutations in two genes, isocitrate dehydrogenase 1 (IDH1) and IDH2, to nearly three-quarters of several of the most common types of brain cancers known as gliomas.

Mutations were found by amplifying sections of the IDH1 and IDH2 genes through polymerase chain reaction (PCR), a process that replicated bits of DNA to levels that were detected by sensitive computer equipment. IDH1 and IDH2 gene alterations were identified in material taken from 500 brain tumors and 500 non-central nervous system cancers. Changes in the IDH1 gene were located in more than 70 % of three common types of gliomas: low-grade astrocytomas, oligodendrogliomas, and secondary glioblastomas. The changes occurred within a single spot along a string of thousands of genetic coding letters. Some of the brain cancers that did not have alterations in IDH1 had equivalent mutations in the closely related gene, IDH2.

Investigators at the Johns Hopkins Kimmel Cancer Center (Baltimore, MD, USA) and Duke University Medical Center (Durham, NC, USA) who performed the study said that further examination of the genes could lead to more precise diagnosis and treatments of the gliomas.

"Pathologists may find it useful to determine IDH1/IDH2 status to help identify and classify these cancers," said D. Williams Parsons, M.D., Ph.D., visiting professor in pediatric oncology at Johns Hopkins and assistant professor at Baylor College of Medicine (Houston, TX, USA). He added that proper diagnosis is essential because treatments differ within types of gliomas, as well as other forms of brain cancer.

Related Links:
Johns Hopkins Kimmel Cancer Center
Duke University Medical Center
Baylor College of Medicine