Miller-Dieker syndrome

The Miller-Dieker syndrome, also known as lissencephaly or deletion syndrome of chromosome 17p13.3, it is a genetic disorder of autosomal dominant, characterized by the absence of circunvolunções (gyri) and fissures (grooves) in the cerebral cortex, giving the brain a smooth appearance.

This disorder results from tiny deletions in certain regions of chromosome 17, encompassing the LIS1 gene. Most cases (about 80%) is sporadic, resulting from microdeletions occurred in the gametes, male or female, thus generating an affected individual. In the minority of cases, around 20%, the condition is due to appear to be a parent carrier of a balanced translocation involving chromosome 17.

The frequency of this disorder is very low, it is estimated that affects 1:20.000-50.000 live births.

Patients with the syndrome have a smooth brain, devoid of gyri and sulci. Instead of six layers, the cerebral cortex has only four of these layers, as well as microcephaly. The facial features are peculiar, as sinking of temples, snub nose, vertical striations on the forehead, and small jaw. It is also a delay in growth and mental development and various abnormalities in the brain, heart, kidneys and gastrointestinal tract.

Failure to thrive, feeding difficulties, seizures and reduction of spontaneous activity may also be present, which typically leads to death in infancy carrier.

Diagnosis and Treatment

Diagnosis is based on clinical manifestations, was confirmed by testing for cytogenetic and FISH (Fluorescent in situ hybridization - Hybridization fluorescent in situ). CT and MRI also assist in confirming the diagnosis.

There is no effective treatment for this syndrome, and that it is intended only relieve symptoms of cerebral malformation.