Tuesday, September 16, 2014
A large meta-analysis that included 87,040 individuals has identified 23 new genetic variants for prostate cancer susceptibility, bringing the total number of common genetic variants linked to prostate cancer to 100
Together, these 100 genetic variants may explain 33% of inherited risk for prostate cancer in European men, and there is hope that they may eventually be useful in a screening test. The new findings come from a huge global research effort led by scientists at the Institute of Cancer Research in London, the University of Cambridge, United Kingdom, and the University of Southern California. "The research emphasizes the importance of common genetic variation in the etiology of prostate cancer, and the importance of large-scale international genetics consortia," co–principal investigator Christopher Haiman, ScD, professor of preventive medicine at the Keck School of Medicine of the University of Southern California, said. For the meta-analysis, data were combined from genome-wide association studies in individuals across several populations, which included European (34,379 case patients and 33,164 control individuals), African (5327 case patients and 5136 control individuals), Japanese (2563 case patients and 4391 control individuals), and Latino (1034 case patients and 1046 control individuals) ancestries. The part of the meta-analysis that focused on studies conducted in people with European ancestry identified 15 variants. Although no risk variants were identified in ancestry-specific analyses across the African, Japanese, or Latino ancestries, 7 new variants were identified across the multi-ethnic ancestries, and 1 was identified from an early-onset analysis in men younger than 55 years. Of the 23 variants, 12 risk variants may appear to have functional significance and have the potential to be targeted for therapeutic intervention. The researchers estimated that together, 100 genetic variants that are now known may explain 33% of inherited risk for prostate cancer in European men. In addition, the 10% of men at highest risk are close to 3 times more likely to develop prostate cancer compared with the average individual; the top 1% are approximately 6 times more likely to develop the disease. The 100 genetic variants correlate with risk for prostate cancer in European men. "Since Caucasians in the United States are generally of European descent, these genetic variants can be used to determine risk for prostate cancer in Caucasian Americans. However, different genetic variants are expected for African Americans and Latinos, and these may not overlap with the genetic variants for European men," Dr. Park said.