PDF(Sci-hub)
Abstract：
Variants identified through parent-child trio-WES yield up to 28-55% positive diagnostic rate across a variety of Mendelian disorders, there remain numerous patients who do not receive a genetic diagnosis. Studies showed that some aberrant splicing variants, which are either not readily detectable by WES or could be miss-interpreted by regular detecting pipelines, are highly relevant to human diseases.
We retrospectively investigated the negative molecular diagnostics through trio-WES for 15 genetically undiagnosed patients whose clinical manifestations were highly suspected to be genetic disorders with well-established genotype-phenotype relationships. We scrutinized the synonymous variants from WES data and Sanger sequenced the suspected intronic region for deep intronic variants. The functional consequences of variants were analyzed by in vitro minigene experiments.
Here, we report two abnormal splicing events, one of which caused exon truncating due to the activation of cryptic splicing site by a synonymous variant; the other caused partial intron retention due to the generation of splicing sites by a deep intronic variant.
We suggest that, despite initial negative genetic test results in clinically highly suspected genetic diseases, the combination of predictive bioinformatics and functional analysis should be considered to unveil the genetic etiology of undiagnosed rare diseases.
We retrospectively investigated the negative molecular diagnostics through trio-WES for 15 genetically undiagnosed patients whose clinical manifestations were highly suspected to be genetic disorders with well-established genotype-phenotype relationships. We scrutinized the synonymous variants from WES data and Sanger sequenced the suspected intronic region for deep intronic variants. The functional consequences of variants were analyzed by in vitro minigene experiments.
Here, we report two abnormal splicing events, one of which caused exon truncating due to the activation of cryptic splicing site by a synonymous variant; the other caused partial intron retention due to the generation of splicing sites by a deep intronic variant.
We suggest that, despite initial negative genetic test results in clinically highly suspected genetic diseases, the combination of predictive bioinformatics and functional analysis should be considered to unveil the genetic etiology of undiagnosed rare diseases.
摘要：
通过亲子三联WES识别的变体在各种孟德尔疾病中产生高达28-55％的阳性诊断率，仍然有许多患者没有接受基因诊断。研究表明，一些异常剪接变体，它们要么不容易被WES检测到，要么可能被常规检测管道遗漏解释，与人类疾病高度相关。
我们通过trio-WES对15例基因未确诊患者的阴性分子诊断进行了回顾性研究，这些患者的临床表现高度怀疑是具有确定的基因型-表型关系的遗传性疾病。我们仔细检查了WES数据中的同义变体，并Sanger对可疑的内含子区域进行了深内含子变体测序。通过体外小基因实验分析变体的功能后果。
这里,我们报告了两个异常剪接事件，其中一种由于同义变体激活隐蔽剪接位点而导致外显子截短；另一种由于深层内含子变体产生剪接位点而导致部分内含子保留。
我们建议,尽管在临床高度怀疑的遗传疾病中最初的基因检测结果为阴性，预测生物信息学和功能分析的结合应该被认为是揭示未诊断的罕见疾病的遗传病因。
我们通过trio-WES对15例基因未确诊患者的阴性分子诊断进行了回顾性研究，这些患者的临床表现高度怀疑是具有确定的基因型-表型关系的遗传性疾病。我们仔细检查了WES数据中的同义变体，并Sanger对可疑的内含子区域进行了深内含子变体测序。通过体外小基因实验分析变体的功能后果。
这里,我们报告了两个异常剪接事件，其中一种由于同义变体激活隐蔽剪接位点而导致外显子截短；另一种由于深层内含子变体产生剪接位点而导致部分内含子保留。
我们建议,尽管在临床高度怀疑的遗传疾病中最初的基因检测结果为阴性，预测生物信息学和功能分析的结合应该被认为是揭示未诊断的罕见疾病的遗传病因。
