Scientists analyzing the DNA of families whose men are prone to prostate cancer have found a mutated gene that predisposes them to the disease. It's still unclear how often a mutation in this gene leads to the cancer in men with no family history of the disease, who make up the majority of cases.
The gene encodes a protein that sits on the surface of immune cells called macrophages. Known as a scavenger receptor, the protein binds to a variety of fat-bearing molecules and has been previously associated with hardening of the arteries and heart disease.
A 31-member team of researchers led by Jianfeng Xu of Wake Forest University School of Medicine in Winston-Salem, N.C., took a close look at the immune system gene because it's in a chromosomal region that past studies had linked to prostate cancer. Moreover, there has been some evidence that sexually transmitted infections and aberrant macrophage activity predispose men to prostate cancer.