|
|
||||||||
From the Friedrich Baur Institute (Drs. MüllerFelber, Stucka, Lochmüller, and Abicht, J.S. Müller, G. Mildner, and S. Petrova), Department of Neurology, and Gene Center, Ludwig Maximilians University, Munich; Department of Pediatrics and Pediatric Neurology (Drs. Schara and Mortier), Ruhr University of Bochum; Department of Neurology (Drs. Krampfl and Bufler), Medical University, Hannover; Department of Neuropediatrics (Dr. Petersen), University of Kiel; Department of Pediatrics (Dr. Kurlemann), University of Münster; and Department of Pediatrics (Dr. Huebner), Technical University of Dresden, Germany; and Neuromuscular Unit (Dr. Merlini), Istituto Ortopedico Rizzoli, Bologna, Italy.
Address correspondence and reprint requests to Dr. H. Lochmüller, Genzentrum München, Feodor-Lynen-Str. 25, 81377 München, Germany; e-mail: hanns{at}lmb.uni-muenchen.de
Background: Mutations in various genes of the neuromuscular junction may cause congenital myasthenic syndromes (CMS). Most mutations identified to date affect the
-subunit gene of the acetylcholine receptor (AChR), leading to end-plate AChR deficiency. Recently, three different mutations in the RAPSN gene have been identified in four CMS patients with AChR deficiency.
Objective: To perform mutation analysis of the RAPSN gene in patients with sporadic or autosomal recessive CMS.
Methods: One hundred twenty CMS patients from 110 unrelated families were analyzed for the RAPSN mutation N88K by restriction fragment length polymorphism and sequence analysis.
Results: In 12 CMS patients from 10 independent families, RAPSN N88K was identified either homozygous or heteroallelic to another missense mutation. Symptoms usually started perinatally or in the first years of life. However, one patient did not show any myasthenic symptoms before the third decade. Clinical symptoms typically included bilateral ptosis, weakness of facial, bulbar, and limb muscles, and a favorable response to anticholinesterase treatment. Crisis-like exacerbations with respiratory insufficiency provoked by stress, fever, or infections in early childhood were frequent. All RAPSN N88K families originate from Central or Western European countries. Genotype analysis indicated that they derive from a common ancestor (founder).
Conclusions: The RAPSN mutation N88K is a frequent cause of rapsyn-related CMS in European patients. In general, patients (RAPSN N88K) were characterized by mild to moderate myasthenic symptoms with favorable response to anticholinesterase treatment. However, severity and onset of symptoms may vary to a great extent.
This article has been cited by other articles:
![]() |
M. Milone, X. M. Shen, D. Selcen, K. Ohno, J. Brengman, S. T. Iannaccone, C. M. Harper, and A. G. Engel Myasthenic syndrome due to defects in rapsyn: Clinical and molecular findings in 39 patients Neurology, July 21, 2009; 73(3): 228 - 235. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. G. Millichap Gene Mutations in Congenital Myasthenic Syndromes AAP Grand Rounds, September 1, 2007; 18(3): 33 - 33. [Full Text] [PDF] |
||||
![]() |
J. G. Milichap Gene Mutations in Congenital Myasthenic Syndromes AAP Grand Rounds, August 1, 2007; 18(2): 21 - 22. [Full Text] [PDF] |
||||
![]() |
J. S. Muller, A. Herczegfalvi, J. J. Vilchez, J. Colomer, L. L. Bachinski, V. Mihaylova, M. Santos, U. Schara, M. Deschauer, M. Shevell, et al. Phenotypical spectrum of DOK7 mutations in congenital myasthenic syndromes Brain, June 1, 2007; 130(6): 1497 - 1506. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. Palace, D. Lashley, J. Newsom-Davis, J. Cossins, S. Maxwell, R. Kennett, S. Jayawant, Y. Yamanashi, and D. Beeson Clinical features of the DOK7 neuromuscular junction synaptopathy Brain, June 1, 2007; 130(6): 1507 - 1515. [Abstract] [Full Text] [PDF] |
||||
![]() |
G. O. Skeie, H. Aurlien, J. S. Muller, H. Lochmuller, G. Norgard, and L. A. Bindoff Unusual features in a boy with the rapsyn N88K mutation Neurology, December 26, 2006; 67(12): 2262 - 2263. [Full Text] [PDF] |
||||
![]() |
J. S. Muller, S. K. Baumeister, V. M. Rasic, S. Krause, S. Todorovic, K. Kugler, W. Muller-Felber, A. Abicht, and H. Lochmuller Impaired receptor clustering in congenital myasthenic syndrome with novel RAPSN mutations Neurology, October 10, 2006; 67(7): 1159 - 1164. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. S. Muller, S. K. Baumeister, U. Schara, J. Cossins, S. Krause, M. v. d. Hagen, A. Huebner, R. Webster, D. Beeson, H. Lochmuller, et al. CHRND mutation causes a congenital myasthenic syndrome by impairing co-clustering of the acetylcholine receptor with rapsyn Brain, October 1, 2006; 129(10): 2784 - 2793. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. Cossins, G. Burke, S. Maxwell, H. Spearman, S. Man, J. Kuks, A. Vincent, J. Palace, C. Fuhrer, and D. Beeson Diverse molecular mechanisms involved in AChR deficiency due to rapsyn mutations Brain, October 1, 2006; 129(10): 2773 - 2783. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. Rodova, K. F. Kelly, M. VanSaun, J. M. Daniel, and M. J. Werle Regulation of the Rapsyn Promoter by Kaiso and {delta}-Catenin Mol. Cell. Biol., August 15, 2004; 24(16): 7188 - 7196. [Abstract] [Full Text] [PDF] |
||||
![]() |
J S Muller, A Abicht, G Burke, J Cossins, P Richard, S K Baumeister, R Stucka, B Eymard, D Hantai, D Beeson, et al. The congenital myasthenic syndrome mutation RAPSN N88K derives from an ancient Indo-European founder J. Med. Genet., August 1, 2004; 41(8): e104 - e104. [Full Text] [PDF] |
||||
![]() |
K Ohno and A G Engel Lack of founder haplotype for the rapsyn N88K mutation: N88K is an ancient founder mutation or arises from multiple founders J. Med. Genet., January 1, 2004; 41(1): e8 - 8. [Full Text] [PDF] |
||||
![]() |
G. Burke, J. Cossins, S. Maxwell, G. Owens, A. Vincent, S. Robb, M. Nicolle, D. Hilton-Jones, J. Newsom-Davis, J. Palace, et al. Rapsyn mutations in hereditary myasthenia: Distinct early- and late-onset phenotypes Neurology, September 23, 2003; 61(6): 826 - 828. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |