Madisons Foundation - Moms And Dads In Search Of Needed Support

What

Miller-Dieker syndrome is a genetic disorder involving the incomplete development of the brain. This disorder is characterized by lissencephaly, which is an increased smoothness of the brain's surface. Normally, the brain's surface is not smooth and has many distinct grooves and folds. Individuals with Miller-Dieker syndrome also have a certain facial appearance, a small head, delayed growth and mental development, neurological complications, and abnormalities of the brain, kidneys, heart, and gastrointestinal tract.

Who

Miller-Dieker syndrome is inherited as an autosomal recessive trait. A child receives two copies of every gene, one from each parent. In order for a child to be affected by Miller-Dieker syndrome the child must inherit two copies of the abnormal gene, one from each parent. Even though each parent carries the gene for this disease they are not affected with Miller-Dieker syndrome because they each have a second, normal copy of the gene. When both parents have one normal gene and one altered gene, each child they conceive has a 25% chance of receiving two altered copies, which results in disease.

Signs and Symptoms

Facial features:

• Small head
• Prominent forehead
• Hollowing of the temples
• Long philtrum (the area between the nose and the upper lip)
• Small upper lip
• Late tooth eruption
• Short nose
• Malpositioned or malformed ears

Other features:

• lissencephaly (abnormally smooth surface of the brain)
• epilepsy
• Mental and growth retardation
• Abnormalities in the brain, kidneys, heart, genitourinary system and gastrointestinal tract
• Hand and foot abnormalities
• Early hypotonia (decreased muscle tone), then subsequent hypertonia (increased muscle tone).

Possible Causes

Miller-Dieker syndrome is due to a deletion, or missing piece, of the LIS 1 gene located on chromosome 17. Genes direct the development and function of every cell in the body. A loss of genetic material contained within this gene causes the failure of certain nerve cells, which are important in the development of the normal brain.

Diagnosis

Miller-Dieker syndrome can be diagnosed using a special molecular genetic test called fluorescent in situ hybridization (FISH). This test identifies whether or not there is an abnormality on chromosome 17. Most major medical centers are able to perform this test.

Treatment

Treatment depends on the severity of the symptoms the child develops over time. Medical therapies are available to treat epilepsy, as well as the complications affecting the kidneys, heart, and intestinal tract. Because these children do not grow well, they may benefit from a feeding tube to correct feeding problems, poor nutrition, and repeated bouts of pneumonia. Special education programs at school assist the child to reach their highest potential.  If the child has severe malformations of the brain, most likely the child will not respond well to treatment.

Prognosis

 The prognosis for development varies depending on the degree of brain malformation. While some individuals may have brain development and intelligence that is almost normal, most children with this disorder have very poor development. Many individuals with lissencephaly die before the age of 2 years due to respiratory disease.

Connect with other parents

In the spirit of community and support, Madisons Foundation offers the unique service of connecting parents of children with rare diseases. If you would like to be connected to other parents of children with this disease, please fill out this brief form.

Weblinks

Birth Disorder Information Directory
http://www.bdid.com/millerdieker.htm
A nice listing of weblinks providing information about MDS and support for those affected.

Disease Database:

http://www.diseasesdatabase.com/links1.asp?glngUserChoice=29494

Central website to gather general information about the condition.

Geneva Foundation

http://www.gfmer.ch/genetic_diseases_v2/gendis_detail_list.php?cat3=365

Good examples and pictures of an affected child.

Google Search for Miller-Dieker Syndrome

References and Sources

 

National Library of Medicine, www.nlm.nih.gov/mesh/jablonski/syndromes/syndrome456.html

OMIM, www.ncbi.nlm.nih.gov/entrez/dispomim.cgi?id=247200

www.pediatricneuro.com/alfonso/pg47.htm