Identification of four novel mutations in MYO7A gene and their association with nonsyndromic deafness and Usher Syndrome 1B

Abstract

IntroductionMYO7A gene has been shown to be associated with Usher syndrome 1B and nonsyndromic deafness. Although a lot of mutations have been reported in MYO7A gene, novel MYO7A mutations are continuously to be identified. MethodsTargeted next generation sequencing was performed on the two unrelated patients with Usher syndrome 1B and nonsyndromic deafness respectively. The identified mutations from targeted next generation sequencing were further validated by Sanger sequencing, and analyzed by bioinformatics tools, like SIFT, Polyphen-2, PyMOL, I-Mutant 2.0 and so on. ResultsBy analyzing the sequencing data of these two patients, four novel MYO7A mutations were revealed: (i) MYO7A p.Tyr560Ser and p.Ala2039Pro were associated with Usher syndrome 1B. (ii) MYO7A c.2187 + 2_+8 delTGAGCAC and p.Leu728Pro were related to nonsyndromic hearing loss. These mutations were further proved to be possibly disease-causing by segregation analysis, conservation analysis and bioinformatics tools. ConclusionsFour novel MYO7A mutations were identified in the present study. These findings provided new evidence for the genetic counseling of Usher syndrome 1B and nonsyndromic deafness.