Dr. Helen M. Ranney, who studied the genetics of sickle cell disease in the early 1950s, has died at age 89. Ranney developed a way to use a laboratory method called gel electrophoresis to distinguish the uncommon form of hemoglobin, called hemoglobin S, that characterizes the disease. She also undertook a study that uncovered thalassemia, another blood disorder, for the first time in blacks.

Related Summaries