The present invention provides diagnostic methods for detecting congenital heart defects, or increased risk thereof, based on the Nell1 gene, RNA and protein. The methods include obtaining a biological sample and assessing the presence of a mutation in the Nell1 gene, RNA or protein. The presence of a mutation in the Nell1 gene, RNA or protein can be assessed by determining the levels of Nell1 gene, RNA or protein in the biological sample. The present invention further provides therapeutic methods for treating congenital heart defects based on the Nell1 gene, RNA and protein.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH
 This invention was made with Government support under Contract No. DE-AC05-00OR22725 between the United States Department of Energy and UT-Battelle, LLC. The Government has certain rights in this invention.