A Novel mutation of SMN1 Gene causes Spinal Muscular Atrophy type 1

Introduction: Spinal Muscular Atrophy (SMA) is one of the most frequent autosomal recessive diseases, with aprevalence of 1 in 6000 newborns. This report presents a new mutation in the Iranian Azari Turkish female infantwith SMA type 1.Method: She demonstrated the characteristic clinical presentations of SMA type 1. Creatine Phosphokinase(CPK), Electromyography (EMG) testing were performed. Molecular analysis by PCR-RFLP, Next GenerationSequencing (NGS) methods and confirmed by Sanger sequencing.Results: CPK was elevated in the serum and EMG abnormalities of denervation were reported. One homozygousmutation c.549 delC in nucleic acid alteration (p. Lys184Serfs*29 amino acid alteration (RefSeq NM_000344)in exon 5 on SMN1 gene has been detected by NGS method and confirmed by Sanger sequencing. Both parentswere heterozygous for this mutation and in the next pregnancy of this family prenatal diagnosis for this mutationwas applied and fetus was carrier and healthy infant was delivered in term.Conclusion: The mutation is a new nutation and has not been reported for SMA pathogenicity yet.

Keywords:

Spinal Muscular Atrophy , New mutation , SMN1 gene