A gene associated with familial glioma was identified by the Gliogene Consortium, an international team of familial brain tumor researchers, led by 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.
The study, primarily funded by the National Cancer Institute, was published this week in the Journal of the National Cancer Institute, and provides new insights on the hereditability of this type cancer.
In familial glioma there is an abnormal growth of malignant cells in brain tissues, which can appear in two or more members of the same family. Familial glioma is estimated to account for 5% of all brain cancers.
In a recent press release Dr. Bondy explained, “It is widely thought amongst the clinical community that there is no association between family history and development of glioma. 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.”
A total of 435 families with familial glioma were recruited from 14 centers in the United States, Sweden, Denmark, the United Kingdom and Israel. By applying a genetic test called whole exome sequencing in 90 individuals with glioma from 55 families, the researchers identified mutations in the POT1 gene, present in two of the families.
“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.” Dr. Bondy said in the press release. “These members were younger than the ones who developed the disease.”
The mutations found in the POT1 gene are thought to lead to a disruption in a region of the POT1 protein that plays an important role in telomeres, leading them to elongate. Previous studies have found an association between elongated telomeres and some types cancers. Additionally, POT1 has also been found in familial melanoma. In this particular study, the POT1 mutations were correlated with oligodendroglioma, a lower grade glioma that is more vulnerable to radiation therapy.
“We will do additional research to see how frequent the mutation is in familial gliomas and if it is also associated with higher grades of the disease,” Dr. Bondy added in the press release.
The Gliogene Consortium researchers are still recruiting families to enrol in this study. The team is actively investigating POT1 and familial glioma, to gain further insights about this type of cancer and determine which families are at increased risk of developing the disease. Further research is necessary to develop therapeutic agents.