Joubert Syndrome - Jewish Genetic Disease

Description
Joubert Syndrome is an autosomal recessive genetic disorder that is characterized by the underdevelopment or absence of the cerebral vermis. The cerebral vermis is a thin worm shaped structure located between the two hemispheres of the cerebellum. The cerebellum, Latin for “little brain” is the area of the hindbrain that is responsible for controlling coordination, balance and equilibrium as well as skeletal muscle tone.

Symptoms
   • Decreased muscle tone
   • Difficulty swallowing
   • Jerky eye movements (nystagmus)
   • Periods of hyperpnea – rapid breathing- may seem like panting
   • Inability to coordinate voluntary muscle movement
   • Poor mental development
   • Large toes and fingers or polydactyly- extra fingers or toes
   • Abnormalities in the shape of the tongue or cleft lip or palate
   • Abnormal growth of the retina
   • Seizures may occur
   • Kidney failure – as they grow older

Incidence and Carriers
One specific mutation found in the TMEM216 gene on chromosome #11 was found to occur in approximately 1 in 92 Ashkenazi Jewish individuals. This translates to a probability of one in every 8,000 Ashkenazi Jewish couple conceiving a child with Joubert Syndrome.

Testing for one common mutation provides a carrier detection rate of at least 95% in this population.

Joubert syndrome affects approximately one in 100,000 children — which equals to about 40 babies per year in the United States

Treatment
Currently there is no cure for Joubert Syndrome. Treatment is supportive and symptomatic.
Treatment includes the following:
   • Infant stimulation
   • Physical therapy
   • Occupational therapy
   • Speech therapy
   • Monitoring of respiratory status with infants who have breathing abnormalities
   • Screening for progressive eye, liver, and kidney complications done on a regular basis
   • Unconventional therapies such as sensory integration, auditory training, water therapy and horseback therapy have been found to be beneficial.

Testing
Although genetic tests can identify a particular causative gene, they often can not predict the severity of the disease

Genetic testing for Joubert Syndrome is difficult and costly. Cost for this genetic testing can range between $200 - $6000 which may or may not be covered by medical insurance.

Currently it is believed that less than 40% of individuals with Joubert Syndrome will have a mutation identified in one of the 5 known genes. In Ashkenazi Jews one specific mutation was found in the TMEM216 gene on chromosome #11.

Laboratories and Screening
The following laboratories offer genetic testing for Joubert Syndrome 3:
   • United States
   • Israel
   • Europe

UNITED STATES
Denver Genetic Laboratories
UCD DNA Diagnostic Laboratory
12800 East 19th Avenue
Mail Stop 8313
Aurora, CO 80045
Phone: (303) 724-3801 (Main laboratory)
Fax: (303) 724-3802 (HIPAA-secure)

Emory University School of Medicine
Emory Molecular Genetics Laboratory
Atlanta, GA
Phone: (404) 778-8500
Fax: (404) 778-8559
Email: eglgc@emory.edu
Mailing Address
Emory Genetics Laboratory
2165 N. Decatur Road
Decatur, GA 30033

PreventionGenetics
Molecular Diagnostics and BioBanking
3700 Downwind Drive
Marshfield, Wisconsin 54449 USA
Phone: (715) 387-0484
Fax: (715) 384-3661
Web: http://www.preventiongenetics.com

The Victor Center for Jewish Genetic Diseases
Albert Einstein Medical Center
5501 Old York Road, Levy 2 West
Philadelphia, PA 19141
Phone: (215) 456-8722

ISRAEL
The Bnai Zion Medical Center
The Simon Winter Institute for Human Genetics,
47 Eliyahu Golomb, Haifa , 33394
Phone: (+972)-4-835-9851
Phone: (+972)-4-835-9495
Web: http://www.b-zion.org.il

Ha’Emek Medical Center
Molecular Genetics Unit
Afula 18101 , Israel
Phone: (+972) 4-649-5416
Email: morad_kh@clalit.org.il

Sheba Medical Center
The Danek Gertner Institute Human Genetics
Molecular diagnosis Laboratory
Tel Hashomer; Ramat Gan . 52621, Israel
Phone: (+972)3-530-3060
Web: http://www.eng.sheba.co.il

EUROPE
• Germany

GERMANY
Centogene GmbH
Schillingalee 68
18057 Rostock
Germany
Phone: (+49) 381-203652-0
Fax: (+49) 381-203652-19
Email: office@centogene.com

Resources and More
Joubert Syndrome Foundation
President Cheryl Duquette
6931 South Carlinda Avenue
Columbia, MD 21046
Phone: (410) 997-8084
Email: joubert@joubertsyndrome.org
Web: http://www.joubertsyndrome.org

Joubert Research Program
University of Washington
Jennifer C. Dempsey, MPH
Box 356320
1959 NE Pacific St/HSB RR247
Seattle, WA 98195
Toll Free: (800) 246-6312
Fax: (206) 543-3184
Email: joubert@uw.edu

Support Groups
Yahoo Groups – Joubert Syndrome
Web: http://health.groups.yahoo.com/group/joubertsyndrome

Madisons Foundation
P.O. Box 241956
Los Angeles, CA 90024
Phone: (310) 264-0826
Fax: (310) 264-4766
Email: getinfo@madisonsfoundation.org