Firstly, we have shown that the cytotoxic G-allele of the previously described functional (c.371G>C) polymorphism (rs2073342) of RNASE3 predisposes to CM in Ghanaian children and we have identified a risk associated haplotype, GGA including this G-allele together with the G-allele of rs2233860 which is associated with increased levels of soluble ECP, and the A-allele of rs8019343. This evidence concerns the gene RNASE3 and cutaneous mastocytosis.