Ganaha Akira, Hishinuma Eiji, Kaname Tadashi, Hiratsuka Masahiro, Kondo Shunsuke, Tono Tetsuya
Department of Otorhinolaryngology-Head and Neck Surgery, University of Miyazaki, Miyazaki 889-1692, Japan.
Advanced Research Center for Innovations in Next-Generation Medicine, Tohoku University, Sendai 980-8573, Japan.
J Clin Med. 2022 Feb 19;11(4):1099. doi: 10.3390/jcm11041099.
Both Pendred syndrome (PS) and nonsyndromic hearing loss with an enlarged vestibular aqueduct (EVA) are autosomal recessive disorders caused by pathogenic variants. The spectrum of pathogenic variants varies with the ethnic background. Among the patients with EVA in Okinawa, 94% had some combination of NM_000441.2(SLC26A4):c.1707+5G>A and NM_000441.2(SLC26A4):c.2168A>G(p.His723Arg), the two pathogenic variants that are the most common in this population. We identified these two pathogenic variants using a novel genotyping method that employed an allele-specific polymerase chain reaction (PCR) from a gDNA and single-stranded tag hybridization chromatographic printed-array strip (STH-PAS) in DNA samples obtained from 48 samples in Okinawa, including 34 patients with EVA and 14 carriers of c.1707+5G>A or c.2168A>G. In addition, whole blood and saliva samples were used for analysis in this genotyping method with direct PCR. The results of STH-PAS genotyping were consistent with those obtained using standard Sanger sequencing for all samples. The accuracy of the STH-PAS method is 100% under the optimized conditions. STH-PAS genotyping provided a diagnosis in 30 out of 34 patients (88%) in Okinawan patients with EVA in under 3 h. The turn-around time for STH-PAS genotyping used with direct PCR was 2 h as a result of the omission of the DNA extraction and purification steps. Using information about the ethnic distribution of pathogenic variants in the gene, STH-PAS genotyping performs a rapid genetic diagnosis that is simple and has a considerably improved efficiency.
Pendred综合征（PS）和伴有前庭导水管扩大（EVA）的非综合征性听力损失均为致病性变异引起的常染色体隐性疾病。致病性变异的谱因种族背景而异。在冲绳患有EVA的患者中，94%具有NM_000441.2（SLC26A4）：c.1707 + 5G>A和NM_000441.2（SLC26A4）：c.2168A>G（p.His723Arg）的某种组合，这两种致病性变异在该人群中最为常见。我们使用一种新型基因分型方法鉴定了这两种致病性变异，该方法采用等位基因特异性聚合酶链反应（PCR）从基因组DNA（gDNA）进行扩增，并结合单链标签杂交色谱打印阵列条带（STH - PAS），对从冲绳的48个样本中获取的DNA样本进行分析，其中包括34例EVA患者以及14例c.1707 + 5G>A或c.2168A>G的携带者。此外，全血和唾液样本用于这种直接PCR基因分型方法的分析。对于所有样本，STH - PAS基因分型的结果与使用标准桑格测序法获得的结果一致。在优化条件下，STH - PAS方法的准确性为100%。STH - PAS基因分型在不到3小时的时间内为34例冲绳EVA患者中的30例（88%）做出了诊断。由于省略了DNA提取和纯化步骤，与直接PCR一起使用的STH - PAS基因分型的周转时间为2小时。利用该基因中致病性变异的种族分布信息，STH - PAS基因分型可进行快速、简单且效率显著提高的基因诊断。
