Joubert syndrome 2 (JBTS2) in Ashkenazi Jews is associated with a TMEM216 mutation.

Abstract

Patients with Joubert syndrome 2 (JBTS2) suffer from a neurological disease manifested by psychomotor retardation, hypotonia, ataxia, nystagmus, and oculomotor apraxia and variably associated with dysmorphism, as well as retinal and renal involvement. Brain MRI results show cerebellar vermis hypoplasia and additional anomalies of the fourth ventricle, corpus callosum, and occipital cortex. The disease has previously been mapped to the centromeric region of chromosome 11. Using homozygosity mapping in 13 patients from eight Ashkenazi Jewish families, we identified a homozygous mutation, R12L, in the TMEM216 gene, in all affected individuals. Thirty individuals heterozygous for the mutation were detected among 2766 anonymous Ashkenazi Jews, indicating a carrier rate of 1:92. Given the small size of the TMEM216 gene relative to other JBTS genes, its sequence analysis is warranted in all JBTS patients, especially those who suffer from associated anomalies.

• Authors: Simon Edvardson, Avraham Shaag, Shamir Zenvirt, Yaniv Erlich, Gregory J Hannon, Alan L Shanske, John Moshe Gomori, Joseph Ekstein, Orly Elpeleg
• Journal: American journal of human genetics (Am J Hum Genet) Vol. 86 Issue 1 Pg. 93-7 (Jan 2010) ISSN: 1537-6605 [Electronic] United States
• PMID: 20036350 (Publication Type: Journal Article)
• Copyright: 2010 The American Society of Human Genetics. Published by Elsevier Inc.

Topics

• Adolescent
• Adult
• Alleles
• Brain (pathology)
• Child
• Child, Preschool
• DNA Mutational Analysis
• Homozygote
• Humans
• Infant
• Jews
• Magnetic Resonance Imaging (methods)
• Mutation
• Nervous System Diseases (ethnology, genetics)
• Syndrome