Prenatal diagnosis of supernumerary der(22)t(11;22) associated with the Dandy-Walker malformation in a fetus.

We present the first report of prenatally diagnosed Dandy-Walker malformation with the karyotype of partial trisomy 11 and 22 due to familial translocation t(11;22)(q23;q11) inherited in three generations. We demonstrate that the Dandy-Walker malformation can be an associated congenital malformation of supernumerary der(22)t(11;22) syndrome and emphasize the importance of chromosomal analysis and genetic counselling in the obstetric management of prenatally diagnosed Dandy-Walker malformation.