Matching Pairs polycythemia veraOnline version information about thus blood cancer by Kennedy Ellis 1 the mutation in which gene causes this blood cancer 2 what does polycythemia cause? 3 polycythemai vera 4 drawing blood 5 what do you experience? 6 enlarged spleen itchiness, headches, dizziness, bleeding/bruising, weakness, fatigue increased number of red blood cells helps reduce # of RBCs janus kinase 2 (JAK2) helps fight infection and filter unwanted material and gets bigger when there is too much RBCs heart attack or stroke