In an attempt to identify younger men who are at risk for prostate cancer, researchers at Johns Hopkins in Baltimore, MD studied 94 men who had been diagnosed with prostate cancer when they were 55 years old or younger or who had close blood relatives with prostate cancer. Past research led the investigators to suspect that one particular region of the human chromosome, known as 17q21-22, might be the location of one or more prostate cancer susceptibility genes. The team analyzed 200 genes located in this region. They found that four of the 94 men had a mutation on a gene known as HOXB13, which plays an important role in the development of the prostate. These four men were also found to have a total of 18 close male relatives with prostate cancer. Blood tests revealed that every one of these men had the HOXB13 gene mutation — powerful evidence that it might be linked to hereditary prostate cancer. In a larger study of 5,100 men who had been treated for prostate cancer, it was found that 72 of them had the same mutation on the HOXB13 gene. In addition, these men were highly likely to have been diagnosed with prostate cancer at a young age or to have one or more relatives with the disease. For comparison, the team studied 1,400 men who didn’t have prostate cancer. Just one man had the HOXB13 mutation. “This study, which was published in the New England Journal of Medicine, found that men who carry the HOXB13 mutation are up to 20 times more likely than non-carriers to develop prostate cancer. It is important to keep in mind that the mutation discovered on the HOBX13 gene is rare and explains only a small number (between 2%-5%) of prostate cancer patients but it is an excellent example of the use of an individual’s personalized genomic information as a predictor of future health issues.
A brief description of terms as used in discussions about genes and prostate cancer was recently published in the July 13th edition of the Johns Hopkins Health Alerts. (See link).