PDF(Pubmed)
Abstract：
Rare or novel missense variants in large genes such as TTN and NEB are frequent in the general population, which hampers the interpretation of putative disease-causing biallelic variants in patients with sporadic neuromuscular disorders. Often, when the first initial genetic analysis is performed, the reconstructed haplotype, i.e. phasing information of the variants is missing. Segregation analysis increases the diagnostic turnaround time and is not always possible if samples from family members are lacking. To overcome this difficulty, we investigated how well the linked-read technology succeeded to phase variants in these large genes, and whether it improved the identification of structural variants. Linked-read sequencing data of nemaline myopathy, distal myopathy, and proximal myopathy patients were analyzed for phasing, single nucleotide variants, and structural variants. Variant phasing was successful in the large muscle genes studied. The longest continuous phase blocks were gained using high-quality DNA samples with long DNA fragments. Homozygosity increased the number of phase blocks, especially in exome sequencing samples lacking intronic variation. In our cohort, linked-read sequencing added more information about the structural variation but did not lead to a molecular genetic diagnosis. The linked-read technology can support the clinical diagnosis of neuromuscular and other genetic disorders.
摘要：
TTN和NEB等大型基因中罕见或新颖的错义变异在普通人群中很常见，这阻碍了对散发性神经肌肉疾病患者中推定的致病双等位基因变异的解释。通常,当进行第一次初始遗传分析时，重建的单倍型，即缺少变体的相位信息。分离分析增加了诊断周转时间,并且如果缺乏来自家庭成员的样本,则不总是可能的。为了克服这个困难，我们调查了链接阅读技术在这些大基因中的相位变异方面的成功程度，以及它是否改善了结构变体的识别。线虫肌病的链接读取测序数据，远端肌病,分析了近端肌病患者的分期，单核苷酸变体，和结构变体。在所研究的大肌肉基因中，变体定相是成功的。使用具有长DNA片段的高质量DNA样品获得最长的连续相块。纯合性增加了相位块的数量，特别是在缺乏内含子变异的外显子组测序样本中。在我们的队列中，连锁阅读测序增加了有关结构变异的更多信息,但并未导致分子遗传学诊断.链接阅读技术可以支持神经肌肉和其他遗传疾病的临床诊断。
