We analyzed in the present study, for the first time, associations of JAK1 (c.1648+1272G>A, c.991-27C>T), JAK2 (c.-1132G>T, c.-139G>A), and STAT3 (c.*1671T>C, c.-1937C>G) SNVs with CM risk, clinicopathological aspects, and prognosis and conducted functional studies to understand their biological consequences. The gene discussed is JAK1; the disease is cutaneous mastocytosis.