This study will evaluate the role of mutation of genes in congenital heart diseases and study the genotype-phenotype correlation. The central hypothesis is that a significant percentage of congenital heart disease is caused by mutation of genes involved in heart development, and the phenotype with missensed mutations is milder than nonsense mutation. Another hypothesis is that a significant proportion of patients with cardiac malformations will have mutations in their genes. The specific aim is to test the mutations of these genes in patients with congenital heart diseases. The study will provide substantial information to understand how the human heart develops. In the future, prenatal diagnosis could be developed based on this study.