Imbalances of the genetic material are a common cause of birth defects. We have found that there are a many cases where a child with a heart defect and some other birth defects has genetic abnormalities that were missed on clinical testing but picked up when we used a higher resolution research test. Researchers at Baylor are testing a new way to find whether a piece of the genetic material is lost, duplicated, or misspelled. We will see if we can find genes that cause birth defects. We will check thousands of small pieces of the genetic material and will compare children with their parents. Participants are asked to provide a small blood or saliva sample at the time of enrollment, and a brief medical history and family history will be obtained. Your participation in this study will help us understand the genetic basis of these defects.