Analysis of the prostate cancer-susceptibility locus HPC20 in 172 families affected by prostate cancer

A recent study of hereditary prostate cancer has provided evidence for a prostate cancer-susceptibility locus, HPC20, which maps to 20q13. To assess further the potential contribution of this locus to prostate cancer susceptibility, we studied 172 unrelated families affected by prostate cancer, using 17 polymorphic markers across a 98.5-cM segment of chromosome 20 that contains the candidate region. Parametric analysis, allowing for heterogeneity, resulted in an overall HLOD score of 0.09 (P = .39) at D20S171, under the assumption of linkage in 6% of families. Mode-of-inheritance-free analysis of the entire data set resulted in a maximal Z(lr) score of 0.76 (LOD 0.13; P = .22) at the same location. The strongest evidence for linkage was seen in the subset of 16 black families (LOD 0.86; Z(lr) = 1.99; P = .23) between markers D20S893 and D20S120, near the putative location of HPC20. Although some positive results were observed, our linkage study does not provide statistically significant support for the existence of a prostate cancer-susceptibility locus HPC20 at 20q13.