Abstract
OBJECTIVE—Spinocerebellar ataxia type 6 (SCA6) is an autosomal dominant cerebellar ataxia (ADCA) of which the mutation causing the disease has recently been characterised as an expanded CAG trinucleotide repeat in the gene coding for the α1A-subunit of the voltage dependent calcium channel. The aim was to further characterise the SCA6 phenotype METHODS—The SCA6 mutation was investigated in 69 German families with ADCA and 61 patients with idiopathic sporadic cerebellar ataxia and the CAG repeat length of the expanded allele was correlated with the disease phenotype. RESULTS—Expanded alleles were found in nine of 69 families as well as in four patients with sporadic disease. Disease onset ranged from 30 to 71 years of age and was significantly later than in other forms of ADCA. Age at onset correlated inversely with repeat length. The SCA6 phenotype comprises predominantly cerebellar signs in concordance with isolated cerebellar atrophy on MRI. Non-cerebellar systems were only mildly affected with external ophthalmoplegia, spasticity, peripheral neuropathy, and parkinsonism. Neither these clinical signs nor progression rate correlated with CAG repeat length. CONCLUSIONS—This study provides the first detailed characterisation of the SCA6 phenotype. Clinical features apart from cerebellar signs were highly variable in patients with SCA6. By comparison with SCA1, SCA2, and SCA3 no clinical or electrophysiological finding was specific for SCA6. Therefore, the molecular defect cannot be predicted from clinical investigations. In Germany, SCA6 accounts for about 13% of families with ADCA. However, up to 30% of SCA6 kindreds may be misdiagnosed clinically as sporadic disease due to late manifestation in apparently healthy parents. Genetic testing is therefore recommended for the SCA6 mutation also in patients with putative sporadic ataxia.
Full Text
The Full Text of this article is available as a PDF (173.6 KB).
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Benomar A., Krols L., Stevanin G., Cancel G., LeGuern E., David G., Ouhabi H., Martin J. J., Dürr A., Zaim A. The gene for autosomal dominant cerebellar ataxia with pigmentary macular dystrophy maps to chromosome 3p12-p21.1. Nat Genet. 1995 May;10(1):84–88. doi: 10.1038/ng0595-84. [DOI] [PubMed] [Google Scholar]
- Campuzano V., Montermini L., Moltò M. D., Pianese L., Cossée M., Cavalcanti F., Monros E., Rodius F., Duclos F., Monticelli A. Friedreich's ataxia: autosomal recessive disease caused by an intronic GAA triplet repeat expansion. Science. 1996 Mar 8;271(5254):1423–1427. doi: 10.1126/science.271.5254.1423. [DOI] [PubMed] [Google Scholar]
- Catterall W. A. Structure and function of voltage-gated ion channels. Annu Rev Biochem. 1995;64:493–531. doi: 10.1146/annurev.bi.64.070195.002425. [DOI] [PubMed] [Google Scholar]
- Elliott M. A., Peroutka S. J., Welch S., May E. F. Familial hemiplegic migraine, nystagmus, and cerebellar atrophy. Ann Neurol. 1996 Jan;39(1):100–106. doi: 10.1002/ana.410390115. [DOI] [PubMed] [Google Scholar]
- Flanigan K., Gardner K., Alderson K., Galster B., Otterud B., Leppert M. F., Kaplan C., Ptácek L. J. Autosomal dominant spinocerebellar ataxia with sensory axonal neuropathy (SCA4): clinical description and genetic localization to chromosome 16q22.1. Am J Hum Genet. 1996 Aug;59(2):392–399. [PMC free article] [PubMed] [Google Scholar]
- Fletcher C. F., Lutz C. M., O'Sullivan T. N., Shaughnessy J. D., Jr, Hawkes R., Frankel W. N., Copeland N. G., Jenkins N. A. Absence epilepsy in tottering mutant mice is associated with calcium channel defects. Cell. 1996 Nov 15;87(4):607–617. doi: 10.1016/s0092-8674(00)81381-1. [DOI] [PubMed] [Google Scholar]
- Gispert S., Twells R., Orozco G., Brice A., Weber J., Heredero L., Scheufler K., Riley B., Allotey R., Nothers C. Chromosomal assignment of the second locus for autosomal dominant cerebellar ataxia (SCA2) to chromosome 12q23-24.1. Nat Genet. 1993 Jul;4(3):295–299. doi: 10.1038/ng0793-295. [DOI] [PubMed] [Google Scholar]
- Gouw L. G., Kaplan C. D., Haines J. H., Digre K. B., Rutledge S. L., Matilla A., Leppert M., Zoghbi H. Y., Ptácek L. J. Retinal degeneration characterizes a spinocerebellar ataxia mapping to chromosome 3p. Nat Genet. 1995 May;10(1):89–93. doi: 10.1038/ng0595-89. [DOI] [PubMed] [Google Scholar]
- Harding A. E. The clinical features and classification of the late onset autosomal dominant cerebellar ataxias. A study of 11 families, including descendants of the 'the Drew family of Walworth'. Brain. 1982 Mar;105(Pt 1):1–28. doi: 10.1093/brain/105.1.1. [DOI] [PubMed] [Google Scholar]
- Imbert G., Saudou F., Yvert G., Devys D., Trottier Y., Garnier J. M., Weber C., Mandel J. L., Cancel G., Abbas N. Cloning of the gene for spinocerebellar ataxia 2 reveals a locus with high sensitivity to expanded CAG/glutamine repeats. Nat Genet. 1996 Nov;14(3):285–291. doi: 10.1038/ng1196-285. [DOI] [PubMed] [Google Scholar]
- Kawaguchi Y., Okamoto T., Taniwaki M., Aizawa M., Inoue M., Katayama S., Kawakami H., Nakamura S., Nishimura M., Akiguchi I. CAG expansions in a novel gene for Machado-Joseph disease at chromosome 14q32.1. Nat Genet. 1994 Nov;8(3):221–228. doi: 10.1038/ng1194-221. [DOI] [PubMed] [Google Scholar]
- Llinás R., Sugimori M., Hillman D. E., Cherksey B. Distribution and functional significance of the P-type, voltage-dependent Ca2+ channels in the mammalian central nervous system. Trends Neurosci. 1992 Sep;15(9):351–355. doi: 10.1016/0166-2236(92)90053-b. [DOI] [PubMed] [Google Scholar]
- Ophoff R. A., Terwindt G. M., Vergouwe M. N., van Eijk R., Oefner P. J., Hoffman S. M., Lamerdin J. E., Mohrenweiser H. W., Bulman D. E., Ferrari M. Familial hemiplegic migraine and episodic ataxia type-2 are caused by mutations in the Ca2+ channel gene CACNL1A4. Cell. 1996 Nov 1;87(3):543–552. doi: 10.1016/s0092-8674(00)81373-2. [DOI] [PubMed] [Google Scholar]
- Orr H. T., Chung M. Y., Banfi S., Kwiatkowski T. J., Jr, Servadio A., Beaudet A. L., McCall A. E., Duvick L. A., Ranum L. P., Zoghbi H. Y. Expansion of an unstable trinucleotide CAG repeat in spinocerebellar ataxia type 1. Nat Genet. 1993 Jul;4(3):221–226. doi: 10.1038/ng0793-221. [DOI] [PubMed] [Google Scholar]
- Pulst S. M., Nechiporuk A., Nechiporuk T., Gispert S., Chen X. N., Lopes-Cendes I., Pearlman S., Starkman S., Orozco-Diaz G., Lunkes A. Moderate expansion of a normally biallelic trinucleotide repeat in spinocerebellar ataxia type 2. Nat Genet. 1996 Nov;14(3):269–276. doi: 10.1038/ng1196-269. [DOI] [PubMed] [Google Scholar]
- Ranum L. P., Schut L. J., Lundgren J. K., Orr H. T., Livingston D. M. Spinocerebellar ataxia type 5 in a family descended from the grandparents of President Lincoln maps to chromosome 11. Nat Genet. 1994 Nov;8(3):280–284. doi: 10.1038/ng1194-280. [DOI] [PubMed] [Google Scholar]
- Riess O., Laccone F. A., Gispert S., Schöls L., Zühlke C., Vieira-Saecker A. M., Herlt S., Wessel K., Epplen J. T., Weber B. H. SCA2 trinucleotide expansion in German SCA patients. Neurogenetics. 1997 May;1(1):59–64. doi: 10.1007/s100480050009. [DOI] [PubMed] [Google Scholar]
- Ross C. A. When more is less: pathogenesis of glutamine repeat neurodegenerative diseases. Neuron. 1995 Sep;15(3):493–496. doi: 10.1016/0896-6273(95)90138-8. [DOI] [PubMed] [Google Scholar]
- Sanpei K., Takano H., Igarashi S., Sato T., Oyake M., Sasaki H., Wakisaka A., Tashiro K., Ishida Y., Ikeuchi T. Identification of the spinocerebellar ataxia type 2 gene using a direct identification of repeat expansion and cloning technique, DIRECT. Nat Genet. 1996 Nov;14(3):277–284. doi: 10.1038/ng1196-277. [DOI] [PubMed] [Google Scholar]
- Schöls L., Amoiridis G., Epplen J. T., Langkafel M., Przuntek H., Riess O. Relations between genotype and phenotype in German patients with the Machado-Joseph disease mutation. J Neurol Neurosurg Psychiatry. 1996 Nov;61(5):466–470. doi: 10.1136/jnnp.61.5.466. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Schöls L., Gispert S., Vorgerd M., Menezes Vieira-Saecker A. M., Blanke P., Auburger G., Amoiridis G., Meves S., Epplen J. T., Przuntek H. Spinocerebellar ataxia type 2. Genotype and phenotype in German kindreds. Arch Neurol. 1997 Sep;54(9):1073–1080. doi: 10.1001/archneur.1997.00550210011007. [DOI] [PubMed] [Google Scholar]
- Schöls L., Riess O., Schöls S., Zeck S., Amoiridis G., Langkafel M., Epplen J. T., Przuntek H. Spinocerebellar ataxia type 1: Clinical and neurophysiological characteristics in German kindreds. Acta Neurol Scand. 1995 Dec;92(6):478–485. doi: 10.1111/j.1600-0404.1995.tb00484.x. [DOI] [PubMed] [Google Scholar]
- Schöls L., Vieira-Saecker A. M., Schöls S., Przuntek H., Epplen J. T., Riess O. Trinucleotide expansion within the MJD1 gene presents clinically as spinocerebellar ataxia and occurs most frequently in German SCA patients. Hum Mol Genet. 1995 Jun;4(6):1001–1005. doi: 10.1093/hmg/4.6.1001. [DOI] [PubMed] [Google Scholar]
- Stea A., Tomlinson W. J., Soong T. W., Bourinet E., Dubel S. J., Vincent S. R., Snutch T. P. Localization and functional properties of a rat brain alpha 1A calcium channel reflect similarities to neuronal Q- and P-type channels. Proc Natl Acad Sci U S A. 1994 Oct 25;91(22):10576–10580. doi: 10.1073/pnas.91.22.10576. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Stevanin G., Le Guern E., Ravisé N., Chneiweiss H., Dürr A., Cancel G., Vignal A., Boch A. L., Ruberg M., Penet C. A third locus for autosomal dominant cerebellar ataxia type I maps to chromosome 14q24.3-qter: evidence for the existence of a fourth locus. Am J Hum Genet. 1994 Jan;54(1):11–20. [PMC free article] [PubMed] [Google Scholar]
- Subramony S. H., Fratkin J. D., Manyam B. V., Currier R. D. Dominantly inherited cerebello-olivary atrophy is not due to a mutation at the spinocerebellar ataxia-I, Machado-Joseph disease, or Dentato-Rubro-Pallido-Luysian atrophy locus. Mov Disord. 1996 Mar;11(2):174–180. doi: 10.1002/mds.870110210. [DOI] [PubMed] [Google Scholar]
- Takiyama Y., Nishizawa M., Tanaka H., Kawashima S., Sakamoto H., Karube Y., Shimazaki H., Soutome M., Endo K., Ohta S. The gene for Machado-Joseph disease maps to human chromosome 14q. Nat Genet. 1993 Jul;4(3):300–304. doi: 10.1038/ng0793-300. [DOI] [PubMed] [Google Scholar]
- Terwindt G. M., Ophoff R. A., Haan J., Frants R. R., Ferrari M. D. Familial hemiplegic migraine: a clinical comparison of families linked and unlinked to chromosome 19.DMG RG. Cephalalgia. 1996 May;16(3):153–155. doi: 10.1046/j.1468-2982.1996.1603153.x. [DOI] [PubMed] [Google Scholar]
- Vahedi K., Joutel A., Van Bogaert P., Ducros A., Maciazeck J., Bach J. F., Bousser M. G., Tournier-Lasserve E. A gene for hereditary paroxysmal cerebellar ataxia maps to chromosome 19p. Ann Neurol. 1995 Mar;37(3):289–293. doi: 10.1002/ana.410370304. [DOI] [PubMed] [Google Scholar]
- Wenning G. K., Ben Shlomo Y., Magalhães M., Daniel S. E., Quinn N. P. Clinical features and natural history of multiple system atrophy. An analysis of 100 cases. Brain. 1994 Aug;117(Pt 4):835–845. doi: 10.1093/brain/117.4.835. [DOI] [PubMed] [Google Scholar]
- Yakura H., Wakisaka A., Fujimoto S., Itakura K. Letter: Hereditary ataxia and HL-A. N Engl J Med. 1974 Jul 18;291(3):154–155. doi: 10.1056/NEJM197407182910314. [DOI] [PubMed] [Google Scholar]
- Zhuchenko O., Bailey J., Bonnen P., Ashizawa T., Stockton D. W., Amos C., Dobyns W. B., Subramony S. H., Zoghbi H. Y., Lee C. C. Autosomal dominant cerebellar ataxia (SCA6) associated with small polyglutamine expansions in the alpha 1A-voltage-dependent calcium channel. Nat Genet. 1997 Jan;15(1):62–69. doi: 10.1038/ng0197-62. [DOI] [PubMed] [Google Scholar]
- von Brederlow B., Hahn A. F., Koopman W. J., Ebers G. C., Bulman D. E. Mapping the gene for acetazolamide responsive hereditary paryoxysmal cerebellar ataxia to chromosome 19p. Hum Mol Genet. 1995 Feb;4(2):279–284. doi: 10.1093/hmg/4.2.279. [DOI] [PubMed] [Google Scholar]