Study Finds Eight Gene Mutations that Cause Malignant Brain Tumors in Children

Author:  Eanas Aboobaker
Institution:  Duke University

A team of researchers funded by the Canadian Cancer Society have identified eight gene mutations that are believed to be responsible for medulloblastomas, the most common malignant brain tumor in children. These findings are a major step forward because they have improved our understanding of the cause of medulloblastomas, which currently account for over 20% of childhood cancer deaths. The findings of this study were reported today in the online publication of Nature Genetics.

Dr. Michael Taylor, a brain surgeon at Toronto's Hospital for Sick Children, led this study which could help scientists develop more effective treatment options for medulloblastomas. According to Dr. Christine Williams, the Director of Research Programs at the Canadian Cancer Research Institute, "this discovery is very promising and may help researchers develop better, more targeted treatments so that more of these children will survive and fewer will suffer debilitating side effects."

During the study, 220 cases of medulloblastomas were studied and the gene mutations were identified through use of high-resolution single-nucleotide polymorphism (SNP) genotyping. Genotyping is a process that is used to identify the differences in the genetic make-up of different individuals. SNPs are the most common type of genetic variation in the human genome, which account for differences in appearance, personality, and susceptibility to disease among individuals. SNPs have become an extremely valuable tool for identifying genes that are responsible for the development of many diseases, including cancer.

Dr. Taylor and his colleagues believe that when the eight genes they have identified are functioning properly, they code for a protein that signals the brain to stop growing. When the genes are mutated, however, the brain does not receive this signal and cells begin to grow uncontrollably, leading to cancer. The researchers confirmed that these mutations play a role in the development of medulloblastomas by showing that when expression of these genes is restored, the growth of malignant tumors greatly diminishes.

The eight gene mutations identified in the study were not previously thought to be responsible for this childhood brain cancer. According to Paul Northcott, a PhD student in Dr Taylor's lab, "we've learned more from this study about the genetic basis of this disease than from any other previous study."

Written by: Eanas Aboobaker

Edited by: Jess Kloss

Published by: Hoi See Tsao