Cortical Dysgenesis in a Patient with Turner Mosaicism

In a patient with Turner mosaicism who had mental retardation, epilepsy and cerebellar ataxia, MRI showed cerebellar atrophy and a bizarre cortical dysgenesis of the cerebrum, which was considered to comprise a mixture of relatively normal gyri and structures resembling pachygyria and Iissencephaly. The karyotype of the patient was 45.X/47.XXX, but the brain dysgenesis could not be explained solely on the basis of this mosaicism, which is rarely associated with a gross abnormality in brain pathology. Abnormality of the X chromosome seems to have some potential for inducing cortical dysgenesis, and this case may be partially attributable to an abnormal locus on the X chromosome.