IGF1 and Familial prostate cancer: There was some evidence that SNPs in modest linkage disequilibrium with the cis‐variant alter the expression levels of IGF1 and WASHC3. Due to the strong association of rs5742653 with circulating IGF‐I concentrations, it's location within the IGF1 gene region, and the lack of any other biological evidence linking WASHC3 to prostate cancer risk, we consider that the use of this cis‐SNP is valid.