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Mutation update of spinal muscular atrophy in Spain: molecular characterization of 745 unrelated patients and identification of four novel mutations in the SMN1 gene

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Abstract

Spinal muscular atrophy (SMA) is caused by mutations in the SMN1 gene. We have studied the molecular pathology of SMA in 745 unrelated Spanish patients using PCR-RFLP, SMN gene dosage analysis, linkage studies, long-range PCR and direct sequencing. Our systematic approach allowed us to complete genetic testing and risk assessment in 736 SMA patients (98.8%). Females were more frequently affected by the acute form of the disease (type I), whereas chronic forms (type II–III) predominated in males (p < 0.008). Absence of the SMN1 gene was detected in 671 patients (90%), and hybrid SMN1SMN2 genes were observed in 37 cases (5%). Furthermore, we detected 13 small mutations in 28 patients (3.8%), four of which were previously identified in other populations (c.91dupT; c.770_780dup11; p.Tyr272Cys and p.Thr274Ile), while five mutations were found to date only in Spanish patients (c.399_402delAGAG, p.Ile116Phe, p.Gln136Glu, c.740dupC and c.834+2T>G). The c.399_402delAGAG mutation accounted for 1.9% of all Spanish SMA patients. Finally, we discovered four novel mutations: c.312dupA, c.411delT, p.Trp190X and p.Met263Thr. Our results confirm that most SMA cases are due to large genetic rearrangements in the repetitive region of the SMA locus, resulting in absence-dysfunction of the SMN1 gene. By contrast, ancestrally inherited small mutations are responsible for only a small number of cases. Four prevalent changes in exons 3 and 6 (c.399_402delAGAG; c.770_780dup11; p.Tyr272Cys; p.Thr274Ile) accounted for almost 70% of our patients with these subtle mutations. An SMN–SMN dimer model featuring tight hydrophobic-aromatic interactions is proposed to explain the impact of mutations at the C-terminal end of the protein.

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References

  1. Bertrandy S, Burlet P, Clermont O, Huber C, Fondrat C, Thierry-Mieg D, Munnich A, Lefebvre S (1999) The RNA-binding properties of SMN: deletion analysis of the zebrafish orthologue defines domains conserved in evolution. Hum Mol Genet 8:775–782

  2. Bingham PM, Shen N, Rennert H, Rorke LB, Black AW, Marin-Padilla MM, Nordgren RE (1997) Arthrogryposis due to infantile neuronal degeneration associated with deletion of the SMNT gene. Neurology 49:848–851

  3. Brahe C, Clermont O, Zappata S, Tiziano F, Melki J, Neri G (1996) Frameshift mutation in the survival motor neuron gene in a severe case of SMA type I. Human Mol Genet 5:1971–1976

  4. Brichta L, Garbes L, Jedrzejowska M, Grellscheid SN, Holker I, Zimmermann K, Wirth B (2008) Nonsense-mediated messenger RNA decay of survival motor neuron 1 causes spinal muscular atrophy. Hum Genet 123:141–153

  5. Bühler D, Raker V, Lührmann R, Fischer U (1999) Essential role for the tudor domain of SMN in spliceosomal U snRNP assembly: implications for spinal muscular atrophy. Hum Mol Genet 8:2351–2357

  6. Bürglen L, Lefebvre S, Clermont O, Burlet P, Viollet L, Cruaud C, Munnich A, Melki J (1996a) Structure and organization of the human survival motor neurone (SMN) gene. Genomics 32:479–482

  7. Bürglen L, Patel S, Dubowitz V, Melki J, Muntoni F (1996b) A novel point mutation in the SMN gene in a patient with type III spinal muscular atrophy. In: First Congress of the World Muscle Society. Elsevier, Amsterdam, p. S39

  8. Bürglen L, Seroz T, Miniou P, Lefebvre S, Burlet P, Munnich A, Viegas Pequignot E, Egly J, Melki J (1997) The gene encoding p44, a subunit of the transcription factor TFIIH, is involved in large-scale deletions associated with Werding–Hoffman disease. Am J Hum Genet 60:72–79

  9. Bussaglia E, Clermont O, Tizzano E, Lefebvre S, Bürglen L, Cruaud C, Urtizberea JA, Colomer J, Munnich A, Baiget M, Melki J (1995) A frame-shift deletion in the survival motor neuron gene in Spanish spinal muscular atrophy patients. Nat Genet 11:335–337

  10. Camu W, Billiard M (1993) Coexistence of amyotrophic lateral sclerosis and Werdnig-Hoffmann disease within a family. Muscle Nerve 16:569–570

  11. Clermont O, Burlet P, Cruaud C, Bertrandy S, Melki J, Munnich A, Lefebvre S (1997) Mutation analysis of the SMN gene in undeleted SMA patients. Am J Hum Genet 61:A329

  12. Clermont O, Burlet Ph, Benit P, Chanterau D, Saugier-Veber P, Munnich A, Cusin V (2004) Molecular analysis of SMA patients without homozygous SMN1 deletions using a new strategy for identification of SMN1 subtle mutations. Hum Mutat 24:417–427

  13. Cuscó I, Barceló MJ, del Rio E, Martín Y, Hernández-Chico C, Bussaglia E, Baiget M, Tizzano EF (2001) Characterisation of SMN hybrid genes in Spanish SMA patients: de novo, homozygous and compound heterozygous cases. Hum Genet 108:222–229

  14. Cusco I, Barceló MJ, Baiget M, Tizzano EF (2002) Implementation of SMA carrier testing in genetic laboratories: comparison of two methods for quantifying the SMN1 gene. Hum Mutat 20:452–459

  15. Cuscó I, López E, Soler-Botija C, Barceló MJ, Baiget M, Tizzano EF (2003) A genetic and phenotypic analysis in Spanish spinal muscular atrophy patients with c.399_402del AGAG, the most frequently found subtle mutation in the SMN1 gene. Hum Mutat 22:136–143

  16. Cuscó I, Barceló MJ, del Rio E, Baiget M, Tizzano EF (2004) Detection of novel mutations in the SMN Tudor domain in type I SMA patients. Neurology 63:146–149

  17. Cuscó I, Barceló MJ, Rojas-García R, Illa I, Gámez J, Cervera C, Pou A, Izquierdo G, Baiget M, Tizzano EF (2006) SMN2 copy number predicts acute or chronic spinal muscular atrophy but does not account for intrafamilial variability in siblings. J Neurol 253:21–25

  18. Cusin V, Clermont O, Gérard B, Chantereau D, Elion J (2003) Prevalence of SMN1 deletion and duplication in carrier and normal populations: implication for genetic counselling. J Med Genet 40:e39

  19. den Dunnen JT, Antonarakis SE (2000) Mutation nomenclature extensions and suggestions to describe complex mutations: a discussion. Hum Mutat 15:7–12

  20. DiDonato CJ, Morgan K, Carpten JD, Fuerst P, Ingraham SE, Prescott G, McPherson JD, Wirth B, Zerres K, Hurko O, Wasmuth JJ, Mendell JR, Bourghes AH, Simard L (1994) Association between Ag1-CA alleles and severity of autosomal recessive proximal spinal muscular atrophy. Am J Hum Genet 55:1218–1229

  21. Eggermann T, Eggermann K, Elbracht M, Zerres K, Rudnik-Schöneborn S (2008) A new splice site mutation in the SMN1 gene causes discrepant results in SMN1 deletion screening approaches. Neuromuscul Disord 18:146–149

  22. Felkötter M, Scwarzer V, Wirth R, Weinker T, Wirth B (2002) Quantitative analyses of SMN1 and SMN2 based on real-time LightCycler PCR: fast and highly reliable carrier testing and prediction of severity of spinal muscular atrophy. Am J Hum Genet 70:358–368

  23. Gennarelli M, Lucarelli M, Capon F, Pizzuti A, Merlini L, Angelini C, Novelli G, Dallapiccola B (1995) Survival motor neuron gene transcript analysis in muscles from spinal muscular atrophy patients. Biochem Biophys Res Commun 213:342–348

  24. Hahnen E, Schönling J, Rudnik-Schöneborn S, Raschke H, Zerres K, Wirth B (1997) Missense mutations in exon 6 of the survival motor neuron gene in patients with spinal muscular atrophy (SMA). Hum Mol Genet 6:821–825

  25. Hausmanowa-Petrusewicz I, Zaremba J, Borkowska J, Szirkowiec W (1984) Chronic proximal spinal muscular atrophy of childhood and adolescence: sex influence. J Med Genet 21:447–450

  26. Kotani T, Sutomo R, Sasongko TH, Sadewa AH, Gunadi Minato T, Fujii E, Endo S, Lee MJ, Ayaki H, Harada Y, Matsuo M, Nishio H (2007) A novel mutation at the N-terminal of SMN Tudor domain inhibits its interaction with target proteins. J Neurol 254:624–630

  27. Lefebvre S, Bürglen L, Reboullet S, Clermont O, Burlet P, Viollet L, Benichou B, Cruaud C, Millasseau P, Zeviani M, Le Paslier D, Frézal J, Cohen D, Weissenbach J, Munnich A, Melki J (1995) Identification and characterization of a spinal atrophy-determining gene. Cell 80:155–165

  28. Lorson CL, Strasswimmer J, Yao JM, Baleja JD, Hahnen E, Wirth B, Le T, Burghes AH, Androphy EJ (1998) SMN oligomerization defect correlates with spinal muscular atrophy severity. Nat Genet 19:63–66

  29. Mailman MD, Heinz JW, Papp AC, Snyder PJ, Sedra MS, Wirth B, Burghes AH, Prior TW (2002) Molecular analysis of spinal muscular atrophy and modification of the phenotype by SMN2. Genet Med 4:20–26

  30. Martín Y, Valero A, del Castillo E, Pascual SI, Hernández-Chico C (2002) Genetic study of SMA patients without homozygous SMN1 deletions: identification of compound heterozygotes and characterisation of novel intragenic SMN1 mutations. Hum Genet 110:257–263

  31. Melki J, Lefebvre S, Burglen L, Burlet P, Clermont O, Millasseau P, Reboullet S, Benichou B, Zeviani M, Le Paslier D (1994) De novo and inherited deletions of the 5q13 region in spinal muscular atrophies. Science 264:1474–1477

  32. Munsat TM, Davies KE (1992) Meeting report: international SMA consortium meeting. Neuromuscul Disord 2:423–428

  33. Parsons DW, McAndrew PE, Monani UR, Mendell JR, Burghes AH, Prior TW (1996) An 11 base pair duplication in exon 6 of the SMN gene produces a type I spinal muscular atrophy (SMA) phenotype: further evidence for SMN as the primary SMA-determining gene. Hum Mol Genet 5:1727–1732

  34. Parsons DW, McAndrew PE, Allinson PS, Parker WD Jr, Burghes AH, Prior TW (1998a) Diagnosis of spinal muscular atrophy in an SMN non-deletion patient using a quantitative PCR screen and mutation analysis. J Med Genet 35:674–676

  35. Parsons DW, McAndrews PE, Iannaccone ST, Mendell JR, Burghes AH, Prior TW (1998b) Intragenic telSMN mutations: frequency, distribution, evidence of a founder effect, and modification of the spinal muscular atrophy phenotype by cenSMN copy number. Am J Hum Genet 63:1712–1723

  36. Pearn J (1978) Genetic studies of acute infantile spinal muscular atrophy (SMA type I). J Med Genet 15:414–417

  37. Pearn J (1980) Classification of spinal muscular atrophies. Lancet 26:919–922

  38. Prior TW (2007) Spinal muscular atrophy diagnostics. J Child Neurol 22:952–956

  39. Rochette CF, Surch LC, Ray PN, McAndrew PE, Prior TW, Burghes AHM, Vanasse M, Simard LR (1997) Molecular diagnosis of non-deletion SMA patients using quantitative PCR of SMN exon 7. Neurogenetics 1:141–147

  40. Rudnik-Schöneborn S, Forkert R, Hahnen E, Wirth B, Zerres K (1996) Clinical spectrum and diagnostic criteria of infantile spinal muscular atrophy: further delineation on the basis of SMN gene deletion findings. Neuropediatrics 27:8–15

  41. Skordis LA, Dunckley MG, Burglen L, Campbell L, Talbot K, Patel S, Melki J, Davies KE, Dubowitz V, Muntoni F (2001) Characterisation of novel point mutations in the survival motor neuron gene SMN, in three patients with SMA. Hum Genet 108:356–357

  42. Sossi V, Giuli A, Vitali T, Tiziano F, Mirabella M, Antonelli A, Neri G, Brahe C (2001) Premature termination mutations in exon 3 of the SMN1 gene are associated with exon skipping and a relatively mild SMA phenotype. Eur J Hum Genet 9:113–120

  43. Sun Y, Grimmler M, Schwarzer V, Schoenen F, Fischer U, Wirth B (2005) Molecular and functional analysis of intragenic SMN1 mutations in patients with spinal muscular atrophy. Hum Mutat 25:64–71

  44. Talbot K, Ponting CP, Theodosiou AM, Rodrigues NR, Surtees R, Mountford R, Davies KE (1997) Missense mutation clustering in the survival motor neuron gene: a role for a conserved tyrosine and glycine rich region of the protein in RNA metabolism? Hum Mol Genet 6:497–500

  45. Tsai CH, Jong YJ, Hu CJ, Chen CM, Shih MC, Chang CP, Chang JG (2001) Molecular analysis of SMN, NAIP and P44 genes of SMA patients and their families. J Neurol Sci 190:35–40

  46. Van der Steege G, Grootsholten van der Vlies P, Draaijers TG, Osinga J, Cobben JM, Scheffer H, Buys CHCM (1995) PCR-based DNA test to confirm clinical diagnosis of autosomal recessive spinal muscular atrophy. Lancet 345:985–986

  47. Wan L, Ottinger L, Cho S, Dreyfuss G (2008) Inactivation of the SMN complex by oxidative stress. Mol Cell 31:244–254

  48. Wang CH, Papendick BD, Bruinsma P, Day JK (1998) Identification of a novel missense mutation of the SMN(T) gene in two siblings with spinal muscular atrophy. Neurogenetics 1:273–276

  49. Wang J, Dreyfuss G (2001) Characterization of functional domains of the SMN protein in vivo. J Biol Chem 276:45387–45393

  50. Wirth B, Herz M, Wetter A, Moskau S, Hahnen E, Rudnik-Schoneborn S, Wienker T, Zerres K (1999) Quantitative analysis of survival motor neuron copies: identification of subtle SMN1 mutations in patients with spinal muscular atrophy, genotype-phenotype correlation, and implications for genetic counseling. Am J Hum Genet 6:1340–1356

  51. Wirth B (2000) An update of the mutation spectrum of the survival motor neurone gene (SMN1) in autosomal recessive spinal muscular atrophy (SMA). Hum Mutat 15:228–237

  52. Zapletalová E, Hedvicáková P, Kozák L, Vondrácek P, Gaillyová R, Maríková T, Kalina Z, Jüttnerová V, Fajkus J, Fajkusová L (2007) Analysis of point mutations in the SMN1 gene in SMA patients bearing a single SMN1 copy. Neuromuscul Disord 17:476–481

  53. Zerres K, Rudnik-Schöneborn S (1995) Natural history in proximal spinal muscular atrophy. Clinical analysis of 445 patients and suggestions for a modification of existing classifications. Arch Neurol 52:518–523

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Acknowledgments

This work was supported by CIBERER (to L.A. and E. Aller), GENAME Project (to S. Bernal, R.M.H., F.J.M.A., E.G. and A.P.), and FIS05-2416 (to E. Also); Grants: FIS 05-2416 (E.F.T.) and GENAME Project (E.F.T., C·H.C., J.M.M., S. Borrego, J.C., M.R.) We wish to thank the consenting parents and patients who made this study possible. We are indebted to all the colleagues and laboratories that referred samples for this study, in particular to Drs. Jaume Colomer, Manel Roig, Jordi Rosell, Ricardo Rojas, Alfredo Santana and Carlos Vazquez. We are also indebted to Dr. Brunhilde Wirth for providing us anonymous samples of German patients with point mutations, to Dr. Ignasi Gich for helpful comments on data statistics analysis and to Silvia Alcover for technical assistance.

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Correspondence to Eduardo F. Tizzano.

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Alías, L., Bernal, S., Fuentes-Prior, P. et al. Mutation update of spinal muscular atrophy in Spain: molecular characterization of 745 unrelated patients and identification of four novel mutations in the SMN1 gene. Hum Genet 125, 29–39 (2009) doi:10.1007/s00439-008-0598-1

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Keywords

  • Spinal Muscular Atrophy
  • Survival Motor Neuron
  • Spinal Muscular Atrophy Patient
  • SMN1 Gene
  • Spinal Muscular Atrophy Type