Screening for Alpha Thalassemia in Healthy Volunteers

Background: Alpha thalassemia is a blood disorder. It is caused by genetic deletions. Part of the DNA is missing from a group of genes called alpha globin. Alpha thalassemias are some of the most common genetic deletions. We are testing for alpha thalassemia trait. Alpha thalassemia trait is when someone has only two out of the normal four alpha globin genes. In some people, they lead to no symptoms. Others have changes that lead to disease, including mild anemia. Researchers want to learn more about alpha thalassemia and blood vessels. This may allow them to develop new treatments for blood diseases such as sickle cell disease. Objective: To better understand how alpha globin deletions in healthy people affect blood vessels. Eligibility: Healthy volunteers ages 18 50 who self-report African ancestry. Design: Participants will provide a one-time saliva sample. This can be by mail, in-person at a study event, or at NIH. Participants will get a small kit to collect their saliva sample. The kit has easy instructions. The sample does not need to be put in the refrigerator. Participants will spit a small amount of saliva (less than half a teaspoon) into a collection tube. Participants will close the funnel lid tightly, and then unscrew the funnel lid from the tube. They will then close the tube tightly with the small cap provided and shake the tube for 5 seconds. Participants will place the tube in the provided envelope and mail it to NIH. The specimen will be stored and processed in the lab. Participants may be invited to participate in more research studies, whether or not researchers find that they have alpha thalassemia trait.