Scientists have identified a third gene that can cause congenital heart defects, a leading cause of death in newborns.
A malfunctioning version of the gene, called GATA4, can lead to defects in the formation of the walls that separate the four chambers of the heart.
Individuals from families with a history of the common heart defect already are being screened for the mutated gene. Such screenings can prepare them for the possibility their offspring are at risk.
The discovery also could lead to drug or genetic therapies that could fix the problem in fetuses, although such treatments are years away, said study co-author Dr. Deepak Srivastava, of the University of Texas Southwestern Medical Center at Dallas.
Details of the discovery appeared Sunday on the Web site of the journal Nature.
About 25,000 babies born in the United States each year, or as many as one in 125 births, have a heart defect, according to the March of Dimes. Many defects require open heart surgery to repair.
American and Japanese researchers discovered the mutated gene while plumbing the genetic makeups of two multigenerational families plagued by heart defects. GATA4 mutations appeared in all family members with defects, but not in those without, nor did researchers find it in 3,000 unrelated individuals they screened.
The gene, which regulates a host of other genes, is the third known to play a role in heart defects. Researchers believe others remain to be discovered.
Eventually, the gene also could reveal a way of repairing the damage caused by heart attacks in adults, since it appears to regulate heart tissue growth, said Dr. Roberta Williams, a pediatric cardiologist at the University of Southern California who was not connected with the research.
