CRISPR interference (CRISPRi) of the L allele in the VCaP prostate cancer cell line (homozygous for the L allele) reduced IRX4 expression (Fig. 3a) and introducing the L allele into a cell line only carrying S alleles opening the chromatin region and the enhancer activation (increased H3K27ac signal) increase IRX4 expression (Fig. 3c, d). The gene discussed is IRX4; the disease is Familial prostate cancer.