Major strides have been made in understanding cancers of blood cells (termed leukemia). However, recent scientific advances suggest that we do not yet understand the whole picture – new biological molecules that regulate how blood cells are made and renewed are being discovered. Here, we will test whether detecting these molecules can help diagnose or give information on prognosis to patients. We will also conduct experiments to see if these molecules are causally linked to leukemia and if they represent good targets for therapy.