Congenital heart disease (CHD) is the most common birth defect that affects nearly 1 in 100 liveborn infants. Heterotaxy (HTX) is a severe form affecting 3-4% of CHD patients where left- right (LR) asymmetry of internal organs is not established correctly. Epidemiological studies suggest that genetics plays a significant role in CHD. Uncovering the genetic pathogenesis for CHD is essential to provide a more accurate prognosis for CHD-related interventions, assess the risk for neurodevelopmental delays, and counsel families about recurrence risks. However, infants that undergo clinical genetic testing, known mutations and genes that cause CHD are identified in <30% of cases. This issue is exacerbated in patients from racial or ethnic backgrounds that are underrepresented in current genetic databases. The overarching GOAL of this proposal is to address this barrier using a multidisciplinary collaboration between clinicians, bioinformaticians, and basic scientists. Our research has the potential to significantly improve care and outcomes for HTX patients.