Genes can cause heart problems.

Understanding the genetics of heart defects may spur the design of new treatment approaches to heart disease, indicate Eric N. Olson, director of the Nancy B. and Jake L. Hamon Center for Basic Research in Cancer, and Deepak Srivastava, assistant professor of pediatrics, University of Texas Southwestern Medical Center. "Cardiac anomalies represent the largest number of human birth defects," Olson explains. "This reflects the complexity of the events associated with the formation of the cardiovascular system."

The researchers examined the genetic mechanisms that control the stages of heart development, revealing the molecular basis for several heart defects. As understanding of these genetic mechanisms advances, it "may ultimately provide opportunities for genetic testing and intervention," Olson notes. They found defects related to the looping of the cardiac tube on the right (normal development) or left (abnormal development) side of the heart particularly interesting. After a cardiac tube formed - completing one of the earliest stages in heart development - it begins to loop to the right before the heart chambers are formed. This is the first sign of left-right asymmetry in the...