Genetics of Tetralogy of Fallot

Tetralogy of Fallot

Approximately 1 in 100 babies is born with some form of congenital heart disease. Tetralogy of Fallot (TOF) is a common form of congenital heart disease and accounts for approximately 10% of cases of congenital heart disease in the United States.

To learn more about the specifics of tetralogy of Fallot, including information about possible causes and different treatment options, please visit the Boston Children's Hospital website.

Genetics of Tetralogy of Fallot

Tetralogy of Fallot occurs when the heart fails to develop correctly during the first eight weeks of fetal life. This error could be do to genetic factors, environmental factors, or some combination of both. Please click here for a basic introduction to genes, chromosomes, and inheritance.

For the majority of individuals with tetralogy of Fallot, there has been no identified genetic cause. Some individuals may have other birth defects and/or health issues, in addition to TOF, that may be part of a genetic syndrome. In these instances, a few causative genes have been identified. In certain families, there may be more than one individual with TOF or another type of congenital heart disease. Researchers have identified a few genes in these families that appear to cause congenital heart disease, including TOF.