We read with great interest the two excellent case histories of chondroectodermal dysplasia (Ellis-van Creveld syndrome) that were reported recently by Smith and Hand (Pediatrics, 21:298, 1958). We must take issue, however, with the conclusion that "The statistical probability of siblings having the complete tetrad of defects is rather remote...." This conclusion appears to be based on the assumptions that the four members of the tetrad (chondrodysplasia, ectodermal dysplasia, polydactylism and congenital heart disease) are caused by four different genes, and that the characteristic association of abnormalities to form a syndrome is due to linkage.
Case histories of neonates with congenital heart disease.