Department of Human Genetics, University of Ulm, Ulm, Germany.
Background: Several prostate cancer (PCa) susceptibility loci have been reported, but attempts to confirm them in independent data sets have produced inconsistent results. It is not yet clear, how much of this variation is due to differences between different populations. HPCX was originally identified in a combined data set of PCa families from the USA and Scandinavia. Considerable differences in the frequency of linked families were observed in this heterogeneous family sample as well as in following studies.
Methods: In order to estimate the significance of HPCX in the German population, DNA samples from 104 PCa families were genotyped at six polymorphic markers spanning a region of approximately 14 cM on Xq27-28, which includes the proposed HPCX candidate locus.
Results: In the entire data set, a maximum NPL Z score of 1.20 (P = 0.11) at marker DXS984 was observed. Statistically significant evidence for linkage was obtained in the subset of 63 families with early-onset disease (i.e., < or = 65 years) with a maximum NPL Z score of 2.32 (P = 0.009) at the same location.
Conclusion: Our results confirm the existence of a prostate cancer susceptibility gene on Xq27-28 also in the German population.