description | Protein which, if defective, causes heterotaxy, a broad group of disorders caused by failure to correctly establish left-right patterning during embryogenesis with consequent abnormal segmental arrangements of cardiac chambers, vessels, lungs, and/or abdominal organs. Heterotaxy include complex cardiac malformations, situs inversus, situs ambiguus, isomerism. Situs inversus indicates complete left-right reversal of organ position and is not usually associated with structural anomalies. Situs ambiguus is an abnormal arrangement of viscera almost invariably associated with complex cardiovascular malformations as well as anomalies of the spleen and the gastrointestinal system. Isomerism is a defect in asymmetry of paired organs that usually have distinct right and left forms, but in this condition, are mirror images |