Dorothy Y. H. Tuan, PhD, a molecular biologist at the Medical College of Georgia in Augusta, is pondering some basic questions regarding sickle cell disease. If she gets the right answers, she hopes to uncover findings that could lead to a cure or successful treatment of a disease that affects about 72 000 people in the United States—primarily African Americans.
Clinical manifestations of sickle cell disease (or more properly sickle cell anemia) are caused by anemia and vaso-occlusive events causing "crises"—episodes of severe pain, bone infarction, leg ulcers, and, in the long-term, atrophy of the spleen. The disease is caused by a mutation in the β-globin gene that changes the structure of the β-globin protein inducing sickle hemoglobin (HbS). The HbS then polymerizes into long strings when deoxygenated. Cells containing these deformed, sickled HbS can then occlude microvascular circulation.