By Julia Karow
This article was originally published Oct. 15.
Myriad Genetics said last week that it has exclusively licensed from Johns Hopkins University a number of patents covering gene mutations that increase the risk for pancreatic cancer.
The gene, PALB2, was identified as a susceptibility gene for familial pancreatic cancer in an exome sequencing study that was published by Hopkins researchers in Science earlier this year (see In Sequence 3/10/2009).
For their study, the scientists analyzed exome sequence data from a normal germline sample of a single patient with a hereditary form of pancreatic cancer, using Sanger sequencing of PCR amplicons. The cost of the study was on the order of $150,000 to $200,000.
They then filtered the more than 15,000 germline variants in the patient's exome by requiring that they inactivated one allele of a gene, and that the second copy was mutated in the tumor.
PALB2, one of three genes that met those criteria, turned out to be mutated in three of 96 additional familial pancreatic cancer patients, but not in any of more than 1,000 healthy controls.
The study was part of a larger project that involved sequencing the exomes of 24 pancreatic cancers and matched normal controls that was published a year ago.
At the time it was published, Jim Eshleman, an associate professor of pathology and oncology at the Sol Goldman Pancreatic Cancer Research Center at Hopkins, who was involved in the work, told In Sequence that he and his colleagues were tentatively planning to develop a test for the gene. "It's a matter of cost and priorities," he said.
Myriad now plans to develop a "novel molecular diagnostic test" for mutations in PALB2 and additional pancreatic cancer predisposition genes to which it holds patents, saying that such a "predictive medicine product" could be on the market as early as next year.
According to the company, having in mutation in the BRCA2, PALB2, or p16 genes increases the risk of developing pancreatic cancer by age 70 by as much as 10- to 20-fold.
However, PALB2 explains only about 3 percent of hereditary pancreatic cancer, making it the second most common susceptibility gene for the disease after BRCA2, which accounts for up to 10 percent of familial cases, according to Alison Klein, director of the National Familial Pancreas Tumor Registry at Hopkins.
Klein told In Sequence in March that 85 percent of hereditary pancreatic cancer cannot yet be explained today, but she said she was hopeful that exon sequencing approaches might be able to identify additional susceptibility genes.