The introduction of thrombopoietin (TPO) receptor agonists (RA) in the last ten years for different disorders, not only for immune thrombocytopenia (ITP), aplastic anemia (AA), but also for thrombocytopenia after hematopoietic stem cell transplantation (HSCT), open a new therapeutic possibility in ITs [7,8,9,10]. The gene discussed is THPO; the disease is Thrombocytopenia.