This mutant strain, carrying at least two mutations, 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 here. Because G1 sperm were cryopreserved, additional incidental mutations are also segregating in this strain.
Two mutant phenotypes are observed. In the first, associated with the Cfc1 (cripto, FRL-1, cryptic family 1) gene, homozygotes demonstrate Cardiovascular Phenotype: Complex congenital heart defects associated with heterotaxy, such as dextroversion with transposition of the great arteries (TGA), unbalanced atrioventricular ventricular septal defect (AVSD), muscular ventricular septal defects (mVSD), hypoplastic right ventricle (RV), common atrium, right aortic arch (RAA), right atrial isomerism, aberrant right subclavian artery, bilateral patent ductus arteriosus (PDA) forming vascular ring, superior-inferior ventricles, and total anomalous pulmonary venous return (TAPVR, intracardiac type). Abnormal thoracic and abdominal organ situs anomalies, such as dextrogastria, right bronchial isomerism, polysplenia, left liver isomerism, inverted liver lobation, malaligned sternal vertebra, and hypoplastic spleen are also seen.
The b2b2736.2Clo mutation is associated with Persistent truncus arteriosus (PTA, Type 1), atrioventricular ventricular septal defect (AVSD), right aortic arch (RAA), and aberrant left subclavian artery forming vascular ring. Growth retardation, microphthalmia, syndactyly, micrognathia, cleft palate, hypoplastic kidneys, lungs, and thymus.