Brain Tumor Gene Found, Linking Familial Glioma Between Family Members
A gene linked to causing brain tumors in families has been discovered, and researchers believe it’s only the beginning of spotting hereditary mutations. An international team of researchers led by some at the Baylor College of Medicine have found a genetic link associated with hereditary brain tumors called familial glioma. They published their findings in the Journal of the National Cancer Institute.
"I have been researching familial glioma for nearly 30 years, and this study is really the first time we have had a hit when it comes to identifying a gene that is potentially associated with predisposition to the disease," said the study’s lead author Dr. Melissa Bondy, associate director of cancer prevention and population sciences at the NCI-designated Dan L. Duncan Cancer Center at Baylor College of Medicine, in a press release. "We are just learning about the risk of cancer associated with POT1 mutations. Some of the other family members who carry the mutation may develop brain tumors later in life. These members were younger than the ones who developed the disease."
Researchers studied 435 families with glioma from various parts of the world, including the United States, Sweden, Denmark, the UK, and Israel. They closely analyzed each person’s entire genome, which posesses tens of thousands of genes at any given time, looking for links. The team identified mutations in a gene called POT1 in two of the families. One family had six members with the POT1 mutation, with three of them having glioma brain tumors. It was the same case for the second family, except two developed glioma. The gene is thought to disrupt the telomeres, which function as protective caps for the genetic information chromosomes carry.
"It is widely thought among the clinical community that there is no association between family history and development of glioma," Bondy said. "Because we know very little about the contributing genetic factors, when cases occur in two or more family members, it is viewed as coincidental. By understanding more about the genetic link, we hope that one day we can improve treatments and preventive strategies for those with a family history of glioma."
It's estimated that about five percent of glioma brain tumors run in families. Bondy’s team believes this is the beginning of an effort to comb through entire family genomes with the hope of finding glioma risk. Brain tumors that arise from the supportive tissue of the brain are known as gliomas, according to the American Brain Tumor Association. Over 70,000 people are estimated to receive a brain tumor diagnosis this year, and a total of 14,000 patients will die from one. Understanding genetic links in families can help researchers identify the exact mutations that cause gliomas, which is the first step into finding a way to treat them.
Bondy said her research team would perform additional research critical to understanding how frequently a gene mutation appears, and if it affects later stages of the disease. They suspect there may be a number of other genes associated with familial glioma, which is why they need to keep on searching for links.
Source: Bondy M and Plon S, et al. Journal of the National Cancer Institute. 2014.