Joubert syndrome
Joubert syndrome | |
---|---|
Classification and external resources | |
Specialty | medical genetics |
ICD-10 | Q04.3 |
ICD-9-CM | 742.2 |
OMIM | 213300 |
DiseasesDB | 30688 |
MeSH | C536293 |
GeneReviews | |
Orphanet | 475 |
Joubert syndrome is a rare genetic disorder that affects the cerebellum, an area of the brain that controls balance and coordination.
Genetics
A number of mutations have been identified in individuals with Joubert syndrome (JBTS) which allowed for classification of the disorder into subtypes.
Type | OMIM | Gene | Locus | Inheritance | Remarks |
---|---|---|---|---|---|
JBTS1 | 213300 | INPP5E | 9q34.3 | Autosomal recessive | Also known as Cerebellooculorenal syndrome 1 (CORS1) |
JBTS2 | 608091 | TMEM216 | 11q12.2 | Autosomal recessive | Also known as Cerebellooculorenal syndrome 2 (CORS2) |
JBTS3 | 608629 | AHI1 | 6q23.3 | Autosomal recessive | |
JBTS4 | 609583 | NPHP1 | 2q13 | ||
JBTS5 | 610188 | CEP290 NPHP6 |
12q21.32 | Autosomal recessive | |
JBTS6 | 610688 | TMEM67 | 8q22.1 | Autosomal recessive | |
JBTS7 | 611560 | RPGRIP1L | 16q12.2 | ||
JBTS8 | 612291 | ARL13B | 3q11.1 | ||
JBTS9 | 612285 | CC2D2A | 4p15.32 | Autosomal recessive | |
JBTS10 | 300804 | OFD1 | Xp22.2 | X-linked recessive | |
JBTS11 | – | TTC21B | 2q24.3 | ||
JBTS12 | – | KIF7 | 15q26.1 | ||
JBTS13 | 614173 | TCTN1 | 12q24.11 | ||
JBTS14 | 614424 | TMEM237 | 2q33.1 | Autosomal recessive | |
JBTS15 | 614464 | CEP41 | 7q32.2 | Autosomal recessive | |
JBTS16 | 614465 | TMEM138 | 11q12.2 | Autosomal recessive | |
JBTS17 | 614615 | C5ORF42 | 5p13.2 | ||
JBTS18 | 614815 | TCTN3 | 10q24.1 | ||
JBTS19 | – | ZNF423 | 16q12.1 | Autosomal dominant | |
JBTS20 | 614970 | TMEM231 | 16q23.1 | Autosomal recessive | |
611654 | CSPP1,[1][2][3] | 8q13.2 | Autosomal recessive |
Diagnosis
The disorder is characterized by absence or underdevelopment of the cerebellar vermis and a malformed brain stem (molar tooth sign).[4] The most common features include ataxia (lack of muscle control), hyperpnea (abnormal breathing patterns), sleep apnea, abnormal eye and tongue movements, and hypotonia. Other malformations such as extra fingers and toes, cleft lip or palate, tongue abnormalities, and seizures may also occur. Developmental, including cognitive, is always present to some degree. Usually the mental retardation will be present.[5]
Joubert syndrome is one of the many genetic syndromes associated with syndromic retinitis pigmentosa.[6] The syndrome was first identified in 1969 by pioneering pediatric neurologist Marie Joubert in Montreal, Canada, while working at the Montreal Neurological Institute and McGill University.[7]
Treatment
Treatment for Joubert syndrome is symptomatic and supportive.[5] Infant stimulation and physical, occupational, speech and hearing therapy may benefit some patients. Infants with abnormal breathing patterns should be monitored.
JS is associated with progressive worsening for kidneys, the liver and the eyes and thus require regular monitoring.[5]
Prognosis
In a sample of 19 children, a 1997 study found that 3 died before the age of 3, and 2 never learned to walk. The children had various levels of retarded development with developmental quotients from 60 to 85.[8]
Research/Ciliopathy
Research has revealed that a number of genetic disorders, not previously thought to be related, may indeed be related as to their root cause. Joubert syndrome is one such disease. It is a member of an emerging class of diseases called ciliopathies.
The underlying cause of the ciliopathies may be a dysfunctional molecular mechanism in the primary cilia structures of the cell, organelles which are present in many cellular types throughout the human body. The cilia defects adversely affect "numerous critical developmental signaling pathways" essential to cellular development and thus offer a plausible hypothesis for the often multi-symptom nature of a large set of syndromes and diseases.
Currently recognized ciliopathies include Joubert syndrome, primary ciliary dyskinesia (also known as Kartagener Syndrome), Bardet-Biedl syndrome, polycystic kidney disease and polycystic liver disease, nephronophthisis, Alstrom syndrome, Meckel-Gruber syndrome and some forms of retinal degeneration.[9]
Joubert syndrome type 2 is disproportionately frequent among people of Jewish descent; this has been attributed to the resistance to intermarriage of this population.[10]
References
- ↑ Shaheen, R.; Shamseldin, H. E.; Loucks, C. M.; Seidahmed, M. Z.; Ansari, S.; Ibrahim Khalil, M.; Al-Yacoub, N.; Davis, E. E.; Mola, N. A.; Szymanska, K.; Herridge, W.; Chudley, A. E.; Chodirker, B. N.; Schwartzentruber, J.; Majewski, J.; Katsanis, N.; Poizat, C.; Johnson, C. A.; Parboosingh, J.; Boycott, K. M.; Innes, A. M.; Alkuraya, F. S. (2013). "Mutations in CSPP1, Encoding a Core Centrosomal Protein, Cause a Range of Ciliopathy Phenotypes in Humans". The American Journal of Human Genetics. 94 (1): 73–9. doi:10.1016/j.ajhg.2013.11.010. PMID 24360803.
- ↑ Akizu, N.; Silhavy, J. L.; Rosti, R. O.; Scott, E.; Fenstermaker, A. G.; Schroth, J.; Zaki, M. S.; Sanchez, H.; Gupta, N.; Kabra, M.; Kara, M.; Ben-Omran, T.; Rosti, B.; Guemez-Gamboa, A.; Spencer, E.; Pan, R.; Cai, N.; Abdellateef, M.; Gabriel, S.; Halbritter, J.; Hildebrandt, F.; Van Bokhoven, H.; Gunel, M.; Gleeson, J. G. (2013). "Mutations in CSPP1 Lead to Classical Joubert Syndrome". The American Journal of Human Genetics. 94 (1): 80–6. doi:10.1016/j.ajhg.2013.11.015. PMID 24360807.
- ↑ Tuz, K.; Bachmann-Gagescu, R.; o’Day, D. R.; Hua, K.; Isabella, C. R.; Phelps, I. G.; Stolarski, A. E.; o’Roak, B. J.; Dempsey, J. C.; Lourenco, C.; Alswaid, A.; Bönnemann, C. G.; Medne, L.; Nampoothiri, S.; Stark, Z.; Leventer, R. J.; Topçu, M.; Cansu, A.; Jagadeesh, S.; Done, S.; Ishak, G. E.; Glass, I. A.; Shendure, J.; Neuhauss, S. C. F.; Haldeman-Englert, C. R.; Doherty, D.; Ferland, R. J. (2013). "Mutations in CSPP1 Cause Primary Cilia Abnormalities and Joubert Syndrome with or without Jeune Asphyxiating Thoracic Dystrophy". The American Journal of Human Genetics. 94 (1): 62–72. doi:10.1016/j.ajhg.2013.11.019. PMID 24360808.
- ↑ Brancati F, Dallapiccola B, Valente EM (2010). "Joubert Syndrome and related disorders". Orphanet J Rare Dis. 5: 20. doi:10.1186/1750-1172-5-20. PMC 2913941. PMID 20615230.
- 1 2 3 Parisi, Melissa A.; Doherty, Dan; Chance, Phillip F.; Glass, Ian A. (2007-03-21). "Joubert syndrome (and related disorders) (OMIM 213300)". European Journal of Human Genetics. 15 (5): 511–521. doi:10.1038/sj.ejhg.5201648. ISSN 1018-4813.
- ↑ Saraiva, JM; Baraitser, M (1992). "Joubert syndrome: a review". American Journal of Medical Genetics. 43 (4): 726–731. doi:10.1002/ajmg.1320430415. PMID 1341417.
- ↑ Joubert M, Eisenring JJ, Robb JP, Andermann F (September 1969). "Familial agenesis of the cerebellar vermis. A syndrome of episodic hyperpnea, abnormal eye movements, ataxia, and retardation". Neurology. 19 (9): 813–25. doi:10.1212/wnl.19.9.813. PMID 5816874.
- ↑ Steinlin, M.; Schmid, M.; Landau, K.; Boltshauser, E. (1997-08-01). "Follow-Up in Children with Joubert Syndrome". Neuropediatrics. 28 (04): 204–211. doi:10.1055/s-2007-973701. ISSN 0174-304X.
- ↑ Badano, Jose L.; Norimasa Mitsuma; Phil L. Beales; Nicholas Katsanis (September 2006). "The Ciliopathies : An Emerging Class of Human Genetic Disorders". Annual Review of Genomics and Human Genetics. 7: 125–148. doi:10.1146/annurev.genom.7.080505.115610. PMID 16722803. Retrieved 2008-06-15.
- ↑ Gutkind, Lee; Kennedy, Pagan (10 October 2013). An Immense New Power to Heal: The Promise of Personalized Medicine. Underland Press. p. 36. ISBN 978-1-937163-07-5.
External links
- The Joubert Syndrome Foundation Home Page
- NINDS Joubert Syndrome Information Page
- Researchers Identify Joubert Syndrome Genes
- GeneReviews: Joubert syndrome
- University of Washington Joubert Research Program
- NCBI Joubert Syndrome
- Joubert Research Program - Seattle Research Hospital Children's Foundation