Clinical features and analysis of deafness genes in 2 patients from a Chinese family with MYH9 disorder

Abstract

Objective To investigate the clinical features of 2 deafness patients from a family with MYH9 disorder, and search the candidate genes related to deafness for mutation sites in this family. Methods Their detailed medical histories were surveyed. Physical examination, routine blood test, biochemical test, audiological test, and Wright-Giemsa staining and immunofluorescence assay of MYH9 protein in the peripheral blood smears were performed. Genomic DNA was extracted from the peripheral blood samples of 2 patients. More than 100 known genes associated with deafness were sequenced by whole exome sequencing, and the results were confirmed by Sanger sequencing. Results All affected members in this family had the typical triad of giant platelets, thrombocytopenia and neutrophil inclusion bodies, and the pedigree analysis revealed autosomal dominant inheritance. In this study, the 2 deaf patients also suffered from anemia, hyperlipidemia and elevated levels of transaminase. The features of their deafness were postlingual deafness, late-onset and progressive hearing loss, and medium and high frequency dominant sensorineural hearing loss. Whole exome sequencing indicated that the pathogenic mutation site of MYH9 gene was c.G4546C:p.V1516L, and no other pathogenic mutations of known genes involved in deafness were found. Conclusion The deafness phenotype of the 2 patients in this family may be related to the MYH9 pathogenic mutation p.V1516L.

Keywords

• myh9 disorder
• deafness
• sensorineural
• whole exome sequencing
• gene mutation