This A to G point mutation at position 2021 of the Drc1 (dynein regulatory complex subunit 1) cDNA was identified in an ENU screen for recessive cardiovascular development phenotypes in Dr. Cecilia Lo's laboratory, NHLBI Cardiovascular Development Consortium (CvDC). It was recovered from G1 sperm and associated with the phenotype described described here. Because G1 sperm were cryopreserved, additional incidental mutations are also segregating in this strain.
Homozygotes demonstrate heterotaxy with complex congenital heart disease such as transposition of the great arteries (TGA), atrioventricular septal defects (AVSD), dual inferior vena cava (IVC), dual hepatic vein, and azygous venous connection. Immotile/dyskinetic airway cilia are also seen.