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Neurological Sciences

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01-09-2020 | Spinal Muscular Atrophy | Original Article

SMN1 gene copy number analysis for spinal muscular atrophy (SMA) in a Turkish cohort by CODE-SEQ technology, an integrated solution for detection of SMN1 and SMN2 copy numbers and the “2+0” genotype

Authors: Ahmet Cevdet Ceylan, Haktan Bağış Erdem, İbrahim Şahin, Meenal Agarwal

Published in: Neurological Sciences | Issue 9/2020

Abstract

Introduction

Spinal muscular atrophy (SMA) is one of the common autosomal recessive disorders with global heterozygous carrier frequency of 1:50. Due to high carrier frequency, significant morbidity associated with the infantile onset disease and prohibitive cost of recently approved therapy, American College of Medical Genetics and Genomics (ACMG) recommends population based screening for SMA carrier status in eligible individuals in the reproductive age group. CODE-SEQ is a novel proprietary next generation sequencing (NGS) based assay, which is capable of detecting homozygous as well as heterozygous SMN1 exon 7 deletions. Along with the copy number estimation, this assay is capable of detecting single nucleotide polymorphisms (SNPs) associated with silent SMA carrier status or “2+0” genotype.

Methods

We have validated a proprietary CODE-SEQ technology in a blinded cohort of 80 clinically well characterized samples from Turkish population for the detection of SMA carriers as well as affected cases. The results were correlated with gold standard MLPA assay.

Results

The copy numbers in exon 7 of SMN1 gene matched with MLPA results in all 80 samples giving 100% correlation. The assay accurately detected the presence/ absence of SNPs associated with “2+0” genotype in the reference samples. None of the tested clinical samples had these SNPs.

Conclusion

The results of this study support the notion that CODE-SEQ will be extremely useful in detecting SMA genotypes in large-scale population-based screening studies.

Available only for authorised users

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Title: SMN1 gene copy number analysis for spinal muscular atrophy (SMA) in a Turkish cohort by CODE-SEQ technology, an integrated solution for detection of SMN1 and SMN2 copy numbers and the “2+0” genotype
Authors: Ahmet Cevdet Ceylan
Haktan Bağış Erdem
İbrahim Şahin
Meenal Agarwal
Publication date: 01-09-2020
Publisher: Springer International Publishing
Keyword: Spinal Muscular Atrophy
Published in: Neurological Sciences / Issue 9/2020
Print ISSN: 1590-1874
Electronic ISSN: 1590-3478
DOI: https://doi.org/10.1007/s10072-020-04365-x

Keynote webinar | Spotlight on sleep in brain health

Springer Medicine

SMN1 gene copy number analysis for spinal muscular atrophy (SMA) in a Turkish cohort by CODE-SEQ technology, an integrated solution for detection of SMN1 and SMN2 copy numbers and the “2+0” genotype

Abstract

Introduction

Methods

Results

Conclusion

Keynote webinar | Spotlight on sleep in brain health

Springer Medicine

Abstract

Introduction

Methods

Results

Conclusion

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