Genotype-phenotype correlation of survival motor neuron and neuronal apoptosis inhibitory protein genes in spinal muscular atrophy patients from Iran

Authors

1 Medical Genetics Laboratory, Alzahra University Hospital; Pediatric Inherited Disease Research Center, Isfahan University of Medical Sciences, Isfahan, Iran

2 Medical Genetics Laboratory, Alzahra University Hospital, Isfahan University of Medical Sciences, Isfahan, Iran

3 Medical Genetics Laboratory, Alzahra University Hospital; Department of Genetics and Molecular Biology, Medical School, Isfahan University of Medical Sciences, Isfahan, Iran

4 Neurosciences Research Center, Isfahan University of Medical Sciences, Isfahan, Iran

Abstract

Background: Proximal spinal muscular atrophy (SMA) is an autosomal recessive neuromuscular disease characterized by symmetrical proximal muscle weakness and atrophy. According to the severity of the disease and the age of onset, SMA can be divided into three groups. The survival motor neuron (SMN) gene that is located on 5q13 is identified as the disease determining gene. Another gene in this region is neuronal apoptosis inhibitory protein (NAIP), and its functional role in the pathogenesis of SMA has not been fully elucidated. Here, we investigated the correlation between deletions in SMN and NAIP genes with clinical features of SMA patients.
Materials and Methods: In the current study, 71 unrelated Iranian patients were investigated for the detection of deletions in SMN1 and NAIP genes. Polymerase chain reaction (PCR) was used to detect the deletions of exon 4 and 5 of the NAIP gene. Deletions in exon 7 and 8 of SMN1 gene were detected by RFLP-PCR with DraI and DdeI, respectively.
Results: Our results showed that 51 patients have homozygous deletions in SMN1 and/or NAIP genes. Among these 51 patients, deletion in NAIP gene were found in 35 patients (65.7% of type I, 22.5% type II and 11.42% type III).
Conclusion: Defect in SMN1 gene plays a major role in manifesting of the disease and NAIP (4 and 5) gene acts as a modifying factor in severity of symptoms. Correlation between NAIP gene defect and severity of the disease is confirmed. However, the exact role of NAIP gene in SMA has yet to be fully clarified.

Keywords

1. Salahshourifar I, Shafeghati Y, Golkar Z, Najmabadi H. Molecular analysis of the neuronal apoptosis inhibitory protein gene in families with spinal muscular atrophy. Arch Iran Med 2007;10:509-13.  Back to cited text no. 1
[PUBMED]    
2. Pearn J. Classification of spinal muscular atrophies. Lancet 1980;1:919-22.  Back to cited text no. 2
[PUBMED]    
3. Rodrigues NR, Owen N, Talbot K, Patel S, Muntoni F, Ignatius J, et al. Gene deletions in spinal muscular atrophy. J Med Genet 1996;33:93-6.  Back to cited text no. 3
[PUBMED]    
4. Munsat TL, Davies KE. International SMA consortium meeting. (26-28 June 1992, Bonn, Germany). Neuromuscul Disord 1992;2:423-8.  Back to cited text no. 4
[PUBMED]    
5. Zerres K, Rudnik-Schöneborn S, Forkert R, Wirth B. Genetic basis of adult-onset spinal muscular atrophy. Lancet 1995;346:1162.  Back to cited text no. 5
    
6. Zerres K, Rudnik-Schöneborn S. Natural history in proximal spinal muscular atrophy. Clinical analysis of 445 patients and suggestions for a modification of existing classifications. Arch Neurol 1995;52:518-23.  Back to cited text no. 6
    
7. Brzustowicz LM, Lehner T, Castilla LH, Penchaszadeh GK, Wilhelmsen KC, Daniels R, et al. Genetic mapping of chronic childhood-onset spinal muscular atrophy to chromosome 5q11.2-13.3. Nature 1990;344:540-1.  Back to cited text no. 7
    
8. Gilliam TC, Brzustowicz LM, Castilla LH, Lehner T, Penchaszadeh GK, Daniels RJ, et al. Genetic homogeneity between acute and chronic forms of spinal muscular atrophy. Nature 1990;345:823-5.  Back to cited text no. 8
[PUBMED]    
9. Lefebvre S, Bürglen L, Reboullet S, Clermont O, Burlet P, Viollet L, et al. Identification and characterization of a spinal muscular atrophy-determining gene. Cell 1995;80:155-65.  Back to cited text no. 9
    
10. Melki J, Abdelhak S, Sheth P, Bachelot MF, Burlet P, Marcadet A, et al. Gene for chronic proximal spinal muscular atrophies maps to chromosome 5q. Nature 1990;344:767-8.  Back to cited text no. 10
[PUBMED]    
11. Melki J, Sheth P, Abdelhak S, Burlet P, Bachelot MF, Lathrop MG, et al. Mapping of acute (type I) spinal muscular atrophy to chromosome 5q12-q14. The french spinal muscular atrophy investigators. Lancet 1990;336:271-3.  Back to cited text no. 11
[PUBMED]    
12. Burnett BG, Sumner CJ. Targeting splicing in spinal muscular atrophy. Ann Neurol 2008;63:3-6.  Back to cited text no. 12
[PUBMED]    
13. Girardet A, Fernandez C, Claustres M. Efficient strategies for preimplantation genetic diagnosis of spinal muscular atrophy. Fertil Steril 2008;90:443.e7-12.  Back to cited text no. 13
    
14. Spinal Muscular Atrophy. ACOG committee opinion, Americam college of obstetricians and gynecologist. Obstet Gynecol 2009;113:1194-6.  Back to cited text no. 14
[PUBMED]    
15. Anderson K, Talbot K. Spinal muscular atrophies reveal motor neuron vulnerability to defects in ribonucleoprotein handling. Curr Opin Neurol 2003;16:595-9.  Back to cited text no. 15
[PUBMED]    
16. Roy N, Mahadevan MS, McLean M, Shutler G, Yaraghi Z, Farahani R, et al. The gene for neuronal apoptosis inhibitory protein is partially deleted in individuals with spinal muscular atrophy. Cell 1995;80:167-78.  Back to cited text no. 16
[PUBMED]    
17. Velasco E, Valero C, Valero A, Moreno F, Hernández-Chico C. Molecular analysis of the SMN and NAIP genes in Spanish spinal muscular atrophy families and correlation between number of copies of cBCD541 and SMA phenotype. Hum Mol Genet 1996;5:257-63.  Back to cited text no. 17
    
18. Watihayati MS, Zabidi-Hussin AM, Tang TH, Matsuo M, Nishio H, Zilfalil BA. Deletion analyses of SMN1 and NAIP genes in Malaysian spinal muscular atrophy patients. Pediatr Int 2007;49:11-4.  Back to cited text no. 18
[PUBMED]    
19. Mrad R, Dorboz I, Ben Jemaa L, Maazoul F, Trabelsi M, Chaabouni M, et al. Molecular analysis of the SMN1 and NAIP genes in 60 tunisian spinal muscular atrophy patients. Tunis Med 2006;84:465-9.  Back to cited text no. 19
[PUBMED]    
20. Thompson TG, DiDonato CJ, Simard LR, Ingraham SE, Burghes AH, Crawford TO, et al. A novel cDNA detects homozygous microdeletions in greater than 50% of type I spinal muscular atrophy patients. Nat Genet 1995;9:56-62.  Back to cited text no. 20
[PUBMED]    
21. Bürglen L, Seroz T, Miniou P, Lefebvre S, Burlet P, Munnich A, et al. The gene encoding p44, a subunit of the transcription factor TFIIH, is involved in large-scale deletions associated with Werdnig-Hoffmann disease. Am J Hum Genet 1997;60:72-9.  Back to cited text no. 21
    
22. Savas S, Gokgoz N, Kayserili H, Ozkinay F, Yuksel-Apak M and Kirdar B. Screening of deletions in SMN, NAIP and BTF 2p44 genes in Turkish spinal muscular atrophy patients. Hum Hered 2000;50:162-5.  Back to cited text no. 22
    
23. Akutsu T, Nishio H, Sumino K, Takeshima Y, Tsuneishi S, Wada H, et al. Molecular genetics of spinal muscular atrophy: Contribution of the NAIP gene to clinical severity. Kobe J Med Sci 2002;48:25-31.  Back to cited text no. 23
[PUBMED]    
24. Simic G. Pathogenesis of proximal autosomal recessive spinal muscular atrophy. Acta Neuropathol 2008;116:223-34.  Back to cited text no. 24
[PUBMED]    
25. Ma H, Wang Y, Mi Z, Wu Y, Zhao P, Zhao S, Jiang M, Li Y. Study of NAIP gene in spinal muscular atrophy. Chinese journal of medical genetics. 1999;16:97-8.  Back to cited text no. 25
    
26. Omrani O, Bonyadi M, Barzgar M. Molecular analysis of the SMN and NAIP genes in Iranian spinal muscular atrophy patients. Pediatr Int 2009;51:193-6.  Back to cited text no. 26
[PUBMED]    
27. Hasanzad M, Golkar Z, Kariminejad R, Hadavi V, Almadani N, Afroozan F, et al. Deletions in the survival motor neuron gene in Iranian patients with spinal muscular atrophy. Ann Acad Med Singapore 2009;38:139-41.  Back to cited text no. 27
[PUBMED]    
28. Bussaglia E, Clermont O, Tizzano E, Lefebvre S, Bürglen L, Cruaud C, et al. A frame-shift deletion in the survival motor neuron gene in Spanish spinal muscular atrophy patients. Nat Genet 1995;11:335-7.  Back to cited text no. 28
    
29. Chang JG, Jong YJ, Huang JM, Wang WS, Yang TY, Chang CP, et al. Molecular basis of spinal muscular atrophy in Chinese. Am J Hum Genet 1995;57:1503-5.  Back to cited text no. 29
[PUBMED]    
30. Derakhshandeh-Peykar P, Esmaili M, Ousati-Ashtiani Z, Rahmani M, Babrzadeh F, Farshidi S, et al. Molecular analysis of the SMN1 and NAIP genes in Iranian patients with spinal muscular atrophy. Ann Acad Med Singapore 2007;36:937-41.  Back to cited text no. 30
[PUBMED]    
31. Saitoh M, Sakakihara Y, Kobayashi S, Hayashi Y, Yanagisawa M. Correlation between deletion patterns of SMN and NAIP genes and the clinical features of spinal muscular atrophy in Japanese patients. Acta Paediatr Jpn 1997;39:584-9.  Back to cited text no. 31
[PUBMED]    
32. Cho K, Ryu K, Lee E, Won S, Kim J, Yoo OJ, et al. Correlation between genotype and phenotype in Korean patients with spinal muscular atrophy. Mol Cells 2001;11:21-7.  Back to cited text no. 32
[PUBMED]    
33. Samilchuk E, D'Souza B, Bastaki L, al-Awadi S. Deletion analysis of the SMN and NAIP genes in Kuwaiti patients with spinal muscular atrophy. Hum Genet 1996;98:524-7.  Back to cited text no. 33
[PUBMED]    
34. Al Rajeh S, Majumdar R, Awada A, Adeyokunnu A, Al Jumah M, Al Bunyan M, et al. Molecular analysis of the SMN and NAIP genes in Saudi spinal muscular atrophy patients. J Neurol Sci 1998;158:43-6.  Back to cited text no. 34
[PUBMED]    
35. Dastur RS, Gaitonde PS, Khadilkar SV, Udani VP, Nadkarni JJ. Correlation between deletion patterns of SMN and NAIP genes and the clinical features of spinal muscular atrophy in Indian patients. Neurol India 2006;54:255-9.  Back to cited text no. 35
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