Nam Gi-Sung, Rim John Hoon, Choi Jae Young, Gee Heon Yung, Choi Jong Rak, Lee Seung-Tae, Jung Jinsei
Department of Otorhinolaryngology, Yonsei University College of Medicine, Seoul, 03722, Republic of Korea.
Department of Pharmacology, Brain Korea 21 PLUS Project for Medical Sciences, Yonsei University College of Medicine, Seoul, 03722, Republic of Korea.
BMC Med Genet. 2019 Apr 1;20(1):57. doi: 10.1186/s12881-019-0775-1.
Many mutations in the α-tectorin gene (TECTA) have been reported to cause non-syndromic hearing loss (NSHL) in either a dominant or recessive inheritance pattern. Among the identified TECTA mutations, H1400Y has been associated with NSHL in two independent studies. However, its exact role in contributing to genetic hearing loss remains elusive.
We herein report the whole-exome sequencing of a proband presenting with prelingual, non-progressive, mild-to-moderate hearing loss in a simplex family. By using trio-based whole-exome sequencing, we found two heterozygous mutations of R1890C and H1400Y in the ZP and ZA domains of TECTA, respectively. R1890C, previously reported as a pathogenic autosomal dominant mutation of genetic hearing loss, was found to be inherited in a de novo pattern, causing hearing loss in the proband. By contrast, H1400Y was not segregated in this family, and one family member with normal hearing also carried the H1400Y mutation.
According to the hearing loss-specific American College of Medical Genetics and Genomics (ACMG) guidelines, we conclude that H1400Y should be disqualified as a cause of genetic hearing loss. True pathogenic variants causing genetic hearing loss should be more deliberately reported in accordance with ACMG guidelines.
据报道,α-肌动蛋白基因(TECTA)中的许多突变会以显性或隐性遗传模式导致非综合征性听力损失(NSHL)。在已鉴定的TECTA突变中,H1400Y在两项独立研究中与NSHL相关。然而,其在导致遗传性听力损失的确切作用仍不清楚。
我们在此报告了一个单基因家庭中一名患有语前、非进行性、轻度至中度听力损失的先证者的全外显子组测序结果。通过基于三联体的全外显子组测序,我们分别在TECTA的ZP和ZA结构域中发现了两个杂合突变R1890C和H1400Y。R1890C先前被报道为遗传性听力损失的致病性常染色体显性突变,被发现以新生突变模式遗传,导致先证者听力损失。相比之下,H1400Y在这个家族中没有分离出来,一名听力正常的家庭成员也携带H1400Y突变。
根据听力损失特异性的美国医学遗传学与基因组学学会(ACMG)指南,我们得出结论,H1400Y不应被认定为遗传性听力损失的病因。应根据ACMG指南更审慎地报告导致遗传性听力损失的真正致病变异。