 In recent decades, hematologists have noticed that persons of African descent sometimes have lower white blood cell counts of a certain type, called granulocytes. These cells help to fight infections. The lower number of granulocytes in this situation does not appear to lead to more infections, and these individuals do not have any symptoms. This condition is called benign ethnic neutropenia BEN, and is observed in a small percentage of individuals of African descent. This study will investigate the condition by studying people with and without BEN. 