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.