By sequencing coding regions of more than 200 genes in a previously identified region of linkage at 17q21–22 (Lange et al. 2003; Gillanders et al. 2004; Xu et al. 2005; Lange et al. 2007; Cropp et al. 2011) a rare but recurrent mutation (G84E) in HOXB13 was recently identified in four of 94 probands from prostate cancer families. The gene discussed is HOXB13; the disease is Familial prostate cancer.