Heterotaxy-neural tube defect and holoprosencephaly occurring independently in two sib fetuses

We report an two sib fetuses, products of a consanguineous union, who had m ultiple and apparently unrelated malformations. The first fetus, a female, had trilobed lungs, a single cardiac ventricle, asplenia, situs ambiguus of the liver, and a lumbosacral meningomyelocele. The brain of this fetus was normal. The second fetus, a male, had bilobed lungs, a single cardiac vent ricle, situs solitus of the abdominal organs and spleen, and a semilobar ho loprosencephaly, The occurrence of these malformations in sibs of different sexes and the parental consanguinity suggest a recessive mutation in a gen e responsible for both heterotaxy and midline defects, including holoprosen cephaly, (C) 1999 Wiley-Liss, Inc.