Mouse model of heterotaxy with single ventricle spectrum of cardiac anomalies.
Heterotaxy arises from a failure of the embryo to establish normal left-right asymmetry and is known to affect 3% of infants with congenital heart disease. A recessive mutation causing heterotaxy was recovered in a mouse mutagenesis screen focused on congenital heart defects. Homozygote mutants exhibit abnormal situs in the thoracic and abdominal cavities. Dextrocardia, levocardia, or mesocardia was seen together with right pulmonary isomerism and complex structural heart defects in the single ventricle spectrum. A dominant chamber of left ventricular morphology positioned on the left or right is seen together with transposition of the great arteries. Right atrial isomerism with or without total anomalous pulmonary venous connection was observed in half of the mutants. Because ciliary motion at the embryonic node is required for the specification of laterality, we examined the tracheal epithelia of newborn mice as a proxy for the nodal cilia. However, videomicroscopy showed no defect in ciliary motion. Genome scanning using polymorphic microsatellite markers mapped the mutation to a 3.3 Mb interval on mouse chromosome 7. None of the genes previously described for familial heterotaxy were found in this interval, indicating a novel mutation in this mouse model of heterotaxy.
Laboratory of Developmental Biology, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA.
Christine N
CN
Aune
Bishwanath
B
Chatterjee
Xiao-Qing
XQ
Zhao
Richard
R
Francis
Luciann
L
Bracero
Qing
Q
Yu
Julie
J
Rosenthal
Linda
L
Leatherbury
Cecilia W
CW
Lo
D000015:Abnormalities, Multiple / Q000196:embryology / Q000235:genetics / Q000473:pathology*; D000818:Animals; D000831:Animals, Newborn; D019521:Body Patterning / Q000235:genetics*; D002874:Chromosome Mapping; D033481:Chromosomes, Mammalian; D002923:Cilia / Q000473:pathology; D003914:Dextrocardia / Q000235:genetics / Q000473:pathology; D004195:Disease Models, Animal; D006325:Heart Atria / Q000473:pathology; D006330:Heart Defects, Congenital / Q000196:embryology / Q000235:genetics / Q000473:pathology*; D006352:Heart Ventricles / Q000002:abnormalities; D006720:Homozygote; D007090:Image Interpretation, Computer-Assisted; D021621:Imaging, Three-Dimensional; D007979:Levocardia / Q000235:genetics / Q000473:pathology; D051379:Mice; D008809:Mice, Inbred C3H; D008810:Mice, Inbred C57BL; D008856:Microscopy, Fluorescence; D018715:Microscopy, Video; D009154:Mutation; D010641:Phenotype; D017689:Polydactyly / Q000235:genetics / Q000473:pathology; D011667:Pulmonary Veins / Q000002:abnormalities; D020545:Respiratory Mucosa / Q000473:pathology; D014188:Transposition of Great Vessels / Q000235:genetics / Q000473:pathology