What is 22q11.2 deletion syndrome?
22q11.2 deletion syndrome is a disorder caused by the deletion of a small piece of chromosome 22. The deletion occurs near the middle of the chromosome at a location designated q11.2. The features of this syndrome vary widely, even among affected members of the same family, and involve many parts of the body. Characteristic signs and symptoms include heart defects that are often present from birth, an opening in the roof of the mouth (a cleft palate) or other palate defects, and mild differences in facial features. People with 22q11.2 deletion syndrome often experience recurrent infections caused by problems with the immune system, and some develop autoimmune disorders such as rheumatoid arthritis and Graves’ disease. Affected individuals may also have kidney abnormalities, low levels of calcium in the blood (which can result in seizures), a decrease in blood platelets (thrombocytopenia), significant feeding difficulties, and hearing loss. Skeletal differences are possible, including m
