目的基于耳聋患者的临床表现,选定POU3F4基因作为检测对象,为患者提供病因学诊断。方法对先证者进行全面的体格检查,排除其他器官病变,并进行详细的听力学及颞骨CT检查。提取先证者外周血白细胞基因组DNA,运用聚合酶链反应的方法,对先证者POU3F4基因进行扩增,直接测序法对POU3F4基因进行全部编码序列检测。结果先证者表现出极重度感音神经性聋。颞骨cT显示双侧耳蜗分隔不全、前庭发育不良、内听道底膨大、耳蜗和内听道底相通。基因检测发现该患者POU3F4基因存在一个新的突变(13.530C〉A(p.S177X)),该位点改变导致终止密码子提前出现,使POU3F4转录因子不能发挥其正常的功能。结论通过对该患者POU3F4基因的序列分析,发现了一个明确致病的新的提前终止的突变位点,丰富了POU3F4基因的突变谱。
Objective Base on the clinical manifestations of a deaf patient, POU3F4 gene was detected, and providing the diagnosis of etiology. Methods A comprehensive physical examination was performed for the proband, to exclude other organ' s disfunction, and detailed audiological testing and temporal bone CT scan were performed. Genomic DNA was extract- ed in the proband' s peripheral blood leukocytes. Polymerase chain reactions (PCR) were performed in the coding sequence of POU3F4 gene. Direct DNA sequencing was subsequently applied to screen the entire coding region of the POU3F4 gene. Results The proband was with severe sensorineural hearing loss. Temporal CT showed that bilateral cochlea incomplete parti- tion, vestibule dysplasia, internal auditory canal fundus expand, and the cochlea interlink with the internal auditory canal fun- dus. A novel mutation (c.530C〉A (p.S177X)) in POU3F4 gene was found in the patient, creating an new stop codon and is predicted to results in a truncated protein lacking normal POU3F4 transcription factor function. Conclusion Through analy- sis the POU3F4 gene of the patient, we found a novel mutation causing premature stop codon, contributing to the mutation spectrum of POU3F4 gene.