Molecular genetic testing for hereditary neuromuscular disorders is increasingly used to identify disease subtypes, determine prevalence, and inform management and prognosis, and although many small disease-specific studies have demonstrated the utility of genetic testing, comprehensive data sets are better positioned to assess the complexity of genetic analysis.

Using high depth-of-coverage next-generation sequencing (NGS) with simultaneous detection of sequence variants and copy number variants (CNVs), we tested 25,356 unrelated individuals for subsets of 266 genes.

A definitive molecular diagnosis was obtained in 20% of this cohort, with yields ranging from 4% among individuals with congenital myasthenic syndrome to 33% among those with a muscular dystrophy. CNVs accounted for as much as 39% of all clinically significant variants, with 10% of them occurring as rare, private pathogenic variants. Multigene testing successfully addressed differential diagnoses in at least 6% of individuals with positive results. Even for classic disorders like Duchenne muscular dystrophy, at least 49% of clinically significant results were identified through gene panels intended for differential diagnoses rather than through single-gene analysis. Variants of uncertain significance (VUS) were observed in 53% of individuals. Only 0.7% of these variants were later reclassified as clinically significant, most commonly in RYR1, GDAP1, SPAST, and MFN2, providing insight into the types of evidence that support VUS resolution and informing expectations of reclassification rates.

These data provide guidance for clinicians using genetic testing to diagnose neuromuscular disorders and represent one of the largest studies demonstrating the utility of NGS-based testing for these disorders.

遗传性神经肌肉疾病的分子遗传学检测越来越多地用于识别疾病亚型、确定患病率并为管理和预后提供信息，尽管许多针对特定疾病的小型研究已经证明了基因检测的实用性，但综合数据集更适合评估复杂性的遗传分析。

使用高覆盖深度的下一代测序 (NGS) 并同时检测序列变异和拷贝数变异 (CNV)，我们测试了 25,356 个无关个体的 266 个基因子集。

该队列中有 20% 获得了明确的分子诊断，诊断率从先天性肌无力综合征患者的 4% 到肌营养不良患者的 33% 不等。CNV 占所有临床显着变异的 39%，其中 10% 是罕见的、私有的致病变异。多基因检测成功地解决了至少 6% 的阳性结果个体的鉴别诊断。即使对于像杜氏肌营养不良这样的经典疾病，至少 49% 的临床显着结果是通过用于鉴别诊断的基因组而不是通过单基因分析确定的。在 53% 的个体中观察到具有不确定意义的变异 (VUS)。这些变异中只有 0.7% 后来被重新分类为具有临床意义，最常见于RYR1、GDAP1、SPAST和MFN2，提供对支持 VUS 解决的证据类型的洞察，并告知重新分类率的预期。

这些数据为临床医生使用基因检测诊断神经肌肉疾病提供了指导，并代表了最大的研究之一，证明了基于 NGS 的检测对这些疾病的效用。