A gene known for its ability to form blood vessels has been found to be a key player in a chromosomal abnormality that causes potentially devastating birth defects in the heart and throughout the body. In a study published in the February 2003 issue of Nature Medicine, a group of collaborators from across the globe reports that abnormalities in vascular endothelial growth factor, or VEGF, is a cause of DiGeorge syndrome. The syndrome can cause a wide range of heart defects, many of which are vascular in nature, as well as problems with the thymus and parathyroid gland, craniofacial abnormalities and mental retardation.