Isolated Dandy-Walker malformation: Prenatal diagnosis in two consecutive pregnancies

We report a family with recurrent Dandy-Walker malformation (DWM). The firs t offspring was found prenatally to have isolated DWM at 30 weeks' gestatio n. Ultrasonography at 19 weeks' gestation in the subsequent pregnancy revea led isolated DWM in both dizygotic twins. Chromosome analysis was normal in all three infants, and autopsy confirmed that no other congenital abnormal ities were present. Evidence suggests that rare families transmit the disor der in an autosomal or X-linked recessive pattern, with a high recurrence r isk.