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