Velo-cardio-facial syndrome/DiGeorge syndrome (VCFS/DGS) is a caused by hemizygous 22q11.2 deletions and associated with craniofacial, thymus gland and cardiac outflow tract (OFT) defects. It occurs with a frequency of 1:4000 live births, making it the most frequent deletion syndrome in humans and the most common syndrome with OFT malformations. Over 60-70% have OFT defects. The most severe OFT defects are persistent truncus arteriosus (PTA) (no separation of pulmonary trunk and aorta in the OFT) and tetralogy of Fallot (TOF), while the most common are ventricular septal defects (VSDs). Aortic arch anomalies occur frequently as well, and include interrupted aortic arch type B and right aortic arch, among others. Tissues within the pharyngeal apparatus of the developing embryo form the structures affected in 22q11.2DS patients, including the OFT. Our research focuses on the functions of genes within the 22q11.2 region such as Tbx1, Crkl and Dgcr8. We use mouse models to explore the potential genetic interaction between these genes, their tissue specificity and their downstream genetic pathways for cardiac development. My research program aims to understand the roles of Dgcr8 in the second heart field for heart development.