We found that dual JAK2/ERK1/2 inhibition by 60 mg/kg ruxolitinib bid and 75 mg/kg LTT462 qd abrogated splenomegaly and corrected leukocytosis and thrombocytosis (Fig. 5A-B, Supplementary Fig. 9A). The gene discussed is MAPK3; the disease is Splenomegaly.