Isolated lissencephaly sequence associated with a microdeletion at chromosome 17p13.

DNA markers YNZ22.1, YNH37.3, 144D6 and VAW508 were studied in a patient with the isolated lissencephaly sequence (ILS). A normal karyotype was found in the patient. The DNA of the patient showed deletions of markers YNZ22.1 and YNH37.3. This is the first report of a case of ILS (with grade 3 lissencephaly) with a submicroscopic deletion. The presence of a microdeletion in 17p13 in an ILS patient indicates that Miller-Dieker syndrome and ILS have a common etiology.