Matsson et al. (2008) analyzed the ACTC1 gene in 2 large Swedish families segregating autosomal dominant ASD and identified heterozygosity for a mutation (M123V; 102540.0005) in the 20 available affected individuals. The authors studied 408 additional individuals referred ... Matsson et al. (2008) analyzed the ACTC1 gene in 2 large Swedish families segregating autosomal dominant ASD and identified heterozygosity for a mutation (M123V; 102540.0005) in the 20 available affected individuals. The authors studied 408 additional individuals referred for sporadic congenital heart disease and identified a 17-bp deletion in the ACTC1 gene in a 10-year-old girl with secundum ASD (102540.0006); the mutation was also identified in her clinically unaffected 43-year-old father, who was found to have an abnormal echocardiogram with a posteriorly deviated interventricular septum, believed to be associated with a spontaneously closed perimembranous ventricular septal defect, causing aortic valve regurgitation. Neither mutation was found in 580 control samples.