A multiplex allele specific PCR capillary electrophoresis (mASPCR-CE) assay for simultaneously analysis of SMN1/SMN2/NAIP copy number and SMN1 loss-of-function variants
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Yunli Lai
und
Wanjun Zhou
Abstract
Objectives
Spinal muscular atrophy (SMA) is a severe inherited neuromuscular disorder with a high carrier frequency and incidence rate. An accurate molecular method for SMA genes is crucial in carrier screening, clinical diagnosis, outcome assessment and precision therapies.
Methods
Comprehensively using the multiplex allele specific PCR (mASPCR) and capillary electrophoresis (CE), a novel single tube assay was developed to simultaneously determine the copy number of SMN1/SMN2/NAIP genes and five common loss-of-function variants in SMN1. A total of 283 genotype known subjects were detected to evaluate the accuracy, while 564 clinical random samples were double-blind detected with this assay and MLPA to assess the specificity and sensitivity.
Results
This assay had high accuracy of 100 % consistency with the predetermined values in 283 genotype known subjects. Among 564 clinical random samples, the correlation between this assay and comparative method was 100 %, which showing high specificity and sensitivity.
Conclusions
This mASPCR-CE assay is easy to use and cost-effective, making it suitable for routine use in molecular screening and clinical diagnosis of SMA.
Award Identifier / Grant number: 2023A1515011098, 2022A1515220117 and 2023A15151400
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Research ethics: Not applicable.
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Informed consent: Informed consent was obtained from all individuals included in this study.
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Author contributions: All the authors have accepted responsibility for the entire content of this manuscript and approved its submission.
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Use of Large Language Models, AI and Machine Learning Tools: None declared.
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Conflict of interest: The authors state no conflict of interest.
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Research funding: This study was supported by Basic and Applied Basic Research Foundation of Guangdong Province 2023A1515011098, 2022A1515220117 and 2023A1515140025.
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Data availability: The raw data can be obtained on request from the corresponding author.
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Supplementary Material
This article contains supplementary material (https://doi.org/10.1515/cclm-2025-0175).
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