Genome analysis used to decode brain cancer: study

The most inclusive genetic sketch of a widespread and a lethal type of brain cancer called glioblastoma has been released by US scientists.

US Senator Edward Kennedy is one of the victims of deadly glioblastoma. Glioblastoma victimizes nearly 20,000 Americans annually and causes 13,000 deaths.

The profile of the cancer unveiled by the experts indicates a number of genetic variations associated with the cancer. Experts have identified three mutations which till now had been a mystery, in about three-quarters of tumor samples that were used in the research.

The genetic sketch may also answer why in few cases, initially, standard chemotherapy treatment (temozolomide) works well and later fails to halt the growth of tumor. Actually, this treatment results in formation of more tumors due to occurrence of few DNA mutations that have higher tolerance for this chemotherapy treatment making it a complete failure after some a while.

The study was published in the British journal Nature.

The study gives a new perspective to look at cancer, a techno perspective. The study holds that dynamic and powerful computers can be used to verify the suspect gene in the given samples of a tissue and the complete fingerprints of genomes (each with tens of thousands of genes) in a large number of samples can also be traced.

In an interview, Lynda Chin, a researcher at the Dana-Farber Cancer Institute in Boston and a member of the Cancer Genome Atlas Research Network (TCGA) said the goal is find out an absolute “atlas” for the genetic transformations that occur in glioblastoma.

She added, "It would be essentially like having a full parts list for cars so that you know everything that could go wrong."

The study looked at 206 samples of the American patients in which the TCGA group sequenced 601 suspect genes and compared the infected genes with the healthy tissue genes.

The study linked 3 genes to the cancer- NF1, ERBB2 and PI3, and experts defined these genes as the culprits that cause cancer.

The study also focused on the incongruities that facilitated cancer and experts found three factors- large strings of missing/duplicated genetic code, distortion or inconvenience in the manner the DNA information is "transcribed" to generate proteins in the patient’s body and lastly, the way methyl groups interacted with DNA, which augmented cancer growth.

Researchers said, as soon as Single Molecule Sequencing technology come into play it will become possible and easier to sequence any number of tumor samples.