A follow‐up study of a Chinese family with Waardenburg syndrome type II caused by a truncating mutation of MITF gene

• Published in: Molecular genetics & genomic medicine Vol. 8; no. 12; pp. e1520 - n/a
• Main Authors: Yang, Shuzhi, Wang, Cuicui, Zhou, Chengyong, Kang, DongYang, Zhang, Xin, Yuan, Huijun
• Format: Journal Article
• Language: English
• Published: United States John Wiley & Sons, Inc 01.12.2020; John Wiley and Sons Inc; Wiley
• Subjects: Audiometry; Congenital diseases; Deoxyribonucleic acid; DNA; Females; gene mutation; Genes; Genetic testing; Hearing; Hearing loss; Hearing protection; Melanocytes; Microphthalmia-associated transcription factor; MITF; MITF gene; Mutation; Neural crest; Nonsense mutation; Original; Phenotypes; Skin; Sox10 protein; Waardenburg syndrome; Denmark; China; MITF; hearing loss; Waardenburg syndrome; gene mutation
• ISSN: 2324-9269; 2324-9269
• DOI: 10.1002/mgg3.1520

Background Waardenburg syndrome (WS) is a highly clinically and genetically heterogeneous disease. The core disease phenotypes of WS are sensorineuronal hearing loss and pigmentary disturbance, which are usually caused by the absence of neural crest cell‐derived melanocytes. At present, four subtypes of WS have been defined, which are caused by seven genes. Waardenburg syndrome type 2 (WS2) is one of the most common forms. Two genes, MITF and SOX10, have been found to be responsible for majority of WS2. Methods In this study, we performed a clinical longitudinal follow‐up and mutation screening for a Chinese family with Waardenburg syndrome type II. Results A diversity of clinical manifestations was observed in this WS2 family. In addition to the congenital hearing loss of most affected family members, progressive hearing loss was also found in some WS2 patients. A nonsense mutation of c.328C>T (p.R110X) in MITF was identified in all affected family members. This mutation results in a truncated MITF protein, which is considered to be a disease‐causing mutation. Conclusion These findings offer a better understanding of the spectrum of MITF mutations and highlight the necessity of continuous hearing assessment in WS patients. The present study describes a large Chinese WS2 family with a highly clinical heterogeneity. Clinical longitudinal follow‐up revealed progressive hearing loss in some patients. A nonsense mutation of c.328C>T (p.R110X) in MITF was identified.