Prostate-specific antigen (PSA)2 is the primary biomarker used to screen for prostate cancer. PSA has limited specificity as a marker, however, and it can be increased in multiple noncancerous conditions [e.g., prostatitis, benign prostatic hyperplasia (BPH)] and after prostatic manipulation (e.g., catheterization) (1, 2).
There is now emerging evidence that PSA concentrations may also be affected by genetic variables. Through genome-wide association studies, investigators have identified >30 single-nucleotide polymorphisms (SNPs) that are associated with prostate cancer susceptibility. Eeles et al. reported a strong association of SNPs on chromosomes 10 (rs10993994) and 19 (rs2735839) with PSA concentration and prostate cancer risk (3). It is noteworthy that rs2735839 is located near the KLK33 (kallikrein-related peptidase 3) gene on chromosome 19, which encodes PSA, potentially underlying the relationship.
Loeb S. Germline Sequence Variants and Prostate-Specific Antigen Interpretation. Clinical Chemistry 2012;57(5):662-3. Germline Sequence Variants and Prostate-Specific Antigen Interpretation