In addition to proteins involved in FGF signaling, prokineticin2 (PROK2), prokineticin receptor 2 (PROKR2)16, 17, GNRH1, GNRHR118, KISS1R19, TAC3, TACR320, CHD721, and WDR1122 have also been shown to be mutated in CHH/KS patients. This evidence concerns the gene PROKR2 and cartilage-hair hypoplasia.