(Hans Ulrich Zellweger, 20th century, American paediatrician), rare peroxisomal disorder characterized by deficiency of multiple peroxisomal enzymes with involvement of both grey and white matter. Liver and kidney are also affected. Affected children show profound hypotonia and epileptic seizures and the great majority die within the first year of life.

In the brain MR scan shows neuronal migration disorders with heterotopic grey matter, pachygyria, polymicrogyria and periventricular heterotopias.