一个Pendred综合征家系的临床及SLC26A4基因检测分析

Clinical and Molecular Diagnosis in a Big Chinese Family with Pendred Syndrome

目的探讨Pendred综合征的临床表现及SLC26A4基因检测特点。方法对一个多人患病的Pen-dred综合征家系进行详尽的临床表型分析,并对其中4例耳聋患者进行SLC26A4基因全编码序列及侧翼序列的检测。结果该家系共三代15人,其中6人(40.0%)为耳聋患者,6例均为语前感音神经性聋,2例(Ⅰ-3和Ⅱ-7)表现为言语障碍,5例(Ⅱ-4、Ⅱ-5、Ⅱ-7、Ⅲ-1、Ⅲ-2)伴单纯甲状腺肿大、3例(Ⅱ-5、Ⅲ-1、Ⅲ-2)伴前庭水管扩大。Ⅱ-4、Ⅱ-5、Ⅲ-1和Ⅲ-2这4例耳聋患者中共发现SLC26A4基因四种不同的突变,患病成员中先证者(Ⅲ-1)及其父亲(Ⅱ-4)、母亲(Ⅱ-5)和妹妹(Ⅲ-2)分别具有p.Q514P和p.H723R、p.N392Y和p.H723R、c.1548insC和p.Q514P、p.N392Y和c.1548ins C双等位基因突变。结论该家系先证者及其父母、妹妹分别由SLC26A4基因不同复合杂合突变导致Pendred综合征;在发现的四种突变中,p.Q514P是既往研究未报道的新发突变。

Objective To elucidate the clinical diagnosis and molecular pathogenesis of Pendred syndrome in a big Chinese family. Methods Clinical materials and DNA sample were obtained from the Pendred syndrome family. The exons and the flanking splicing sites of SLC26A4 were screened in the 4 major patients in this family by nested PCR and direct sequencing. Results The clinical characterizations of patients in this family included the prelingual sensorineural hearing loss, dysphonia, goiter, normal thyroid function and enlarged vestibular aqueduct. A total of 4 different types of SLC26A4 mutations were identified in the family. The proband ,his father,his mother and his sister were carried with different SLC26A4 biallelic mutations which were p. Q514P and p. H723R,p. N392Y and p. H723R,c. 1548insC and p. Q514P,p. N392Y and c. 1548insC, respectively. Oonclusien The proband, his father, his mother and his sister with Pendred syndrome were caused by different biallelic mutations of SLC26A4. In the 4 types of SLC26A4 mutations, p. Q514P is novel, which has not been yet reported in the previous literatures.