Yu Jiang , Zhenyu Luo , Wenrong Wang , Xingxiu Lu , ZhongMin Xia , Jieqiong Xie , Mei Lu , Lili Wu , Yulin Zhou , Qiwei Guo
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引用次数: 0
Abstract
Heterozygous carriers of the survival of motor neuron 1 (SMN1) gene deletion in parents account for approximately 95% of neonatal spinal muscular atrophy cases. Given the severity of the disease, professional organizations have recommended periconceptional spinal muscular atrophy carrier screening to all couples, regardless of race or ethnicity. However, the prevalence of screening activities in mainland China remains suboptimal, mainly attributed to the limitations of the existing carrier screening methods. Herein, we aimed to develop a low-cost, accessible, and accurate carrier screening method based on duplex droplet digital PCR (ddPCR), to cover a wider population in developing countries, including China. The receiver operating characteristic curve was used to determine the cut-off value of SMN1 copy numbers. Performance validation was conducted for linearity, precision, and accuracy. In total, 482 cases were considered to validate the concordance between the developed ddPCR assay and multiplex ligation-dependent probe amplification. Linear correlations were excellent between the expected concentration of the reference gene and the observed values (R2 > 0.99). Both the intra- and inter-assay precision of our ddPCR assays were less than 6.0%. The multiplex ligation-dependent probe amplification and ddPCR results were consistent in 480 of the 482 cases (99.6%). Two cases with multiplex ligation-dependent probe amplification, suggestive of two copies of SMN1 exon 7, were classified into three copies by ddPCR analysis. The overall correct classification of the samples included in our ddPCR assay was 100%. This study demonstrates that an appropriate cut-off value is an important prerequisite for establishing a semi-quantitative method to determine the SMN1 copy numbers. Compared to conventional methods, our ddPCR assay is low-cost, highly accurate, and has full potential for application in population spinal muscular atrophy carriers screening.
期刊介绍:
The European Journal of Medical Genetics (EJMG) is a peer-reviewed journal that publishes articles in English on various aspects of human and medical genetics and of the genetics of experimental models.
Original clinical and experimental research articles, short clinical reports, review articles and letters to the editor are welcome on topics such as :
• Dysmorphology and syndrome delineation
• Molecular genetics and molecular cytogenetics of inherited disorders
• Clinical applications of genomics and nextgen sequencing technologies
• Syndromal cancer genetics
• Behavioral genetics
• Community genetics
• Fetal pathology and prenatal diagnosis
• Genetic counseling.