United Diagnostic and Research Center for Clinical Genetics, School of Public Health of Xiamen University & Xiamen Maternal and Child Health Hospital, 361003, Xiamen, Fujian, China.
Department of Dermatology, Zhongshan Hospital Xiamen University, 361004, Xiamen, Fujian, China.
J Hum Genet. 2019 May;64(5):387-396. doi: 10.1038/s10038-019-0576-6. Epub 2019 Feb 15.
Carrier screening of spinal muscular atrophy (SMA) can provide reproductive options for carriers and prevent the birth defects. Here, we developed a simple screening test based on melting analysis. The test comprises a duplex PCR with two primer pairs and three probes to simultaneous amplify SMN1, SMN2, and CFTR. By analyzing the melting profiles, we were able to determine the SMN1/SMN2 ratio and SMN1 + SMN2 copy number to subsequently determine the copy number of SMN1. Samples with one copy of SMN1 were considered as "high risk for carrier," while samples with ≥2 copies of SMN1 were considered as "low risk for carrier." We evaluated the clinical performance of this test using 215 clinical samples with various genotypes that had been previously confirmed by multiplex ligation-dependent probe amplification (MLPA). The test showed high sensitivity (100%) and specificity (97.1%) as well as high positive (97.3%) and negative (100%) predictive value, and was in perfect agreement with the gold standard test, MLPA (k = 0.97). Moreover, it is rapid, inexpensive, and easy to perform and automate, with high reproducibility and capacity. Therefore, we expect this test will advance carrier screening for SMA.
脊髓性肌萎缩症（SMA）的携带者筛查可以为携带者提供生殖选择，并预防出生缺陷。在这里，我们开发了一种基于熔解分析的简单筛查测试。该测试包括一对双 PCR 引物对和三个探针，以同时扩增 SMN1、SMN2 和 CFTR。通过分析熔解曲线，我们能够确定 SMN1/SMN2 比值和 SMN1+SMN2 拷贝数，从而确定 SMN1 的拷贝数。将具有单拷贝 SMN1 的样本视为“高风险携带者”，而具有≥2 拷贝 SMN1 的样本视为“低风险携带者”。我们使用 215 个经过多重连接依赖性探针扩增（MLPA）先前确认的具有各种基因型的临床样本评估了该测试的临床性能。该测试显示出高灵敏度（100%）和特异性（97.1%），以及高阳性（97.3%）和阴性（100%）预测值，与金标准测试 MLPA 完全一致（k=0.97）。此外，它快速、廉价、易于操作和自动化，具有高重复性和容量。因此，我们预计该测试将推进 SMA 的携带者筛查。
