Children carrying either the RTN3 (rs 542998 TC vs. CC OR 1.781, 95% CI 1.276–2.487, p = 0.0006) or the IL-13 (rs 20541 CT vs. TT OR 2.02, 95% CI 1.346–3.03, p = 0.0008) SNPs were more likely than other children to develop CM (Table 2, Figure 2). The gene discussed is IL13; the disease is cutaneous mastocytosis.