Seen in one of six cases of patients with tetralogy of fallot, and not seen in 100 controls. The variant was also seen in an unaffected mother and unaffected grandmother; the authors conclude that this indicates the variant has reduced penetrance. This is not very high significance: p = 0.057 using a two-tailed Fisher’s Exact test.
These authors found this variant in a family with atrial septal defect but no conduction disease, however, they found the variant did not segregate with disease in the family: the affected parent and grandparent were both not carriers, while a carrier sibling was unaffected. The authors conclude that this is probably a non-disease-causing polymorphism.