Analysis and investigation of novel mutations in the SLC26A4 gene causing enlarged vestibular aqueduct
Objective The study aims to investigate SLC26A4 gene mutations in adolescent deaf patients in Handan,Hebei Province,China.It also focuses on exploring the molecular genetics of a child with enlarged vestibular aqueduct to understand the underlying causes of this condition.Methods Blood samples were obtained from 75 individuals from Handan Special Education School and 94 individuals from Handan University who had non-syndromic deafness.The 20 exons of the SLC26A4 gene were amplified using polymerase chain reaction(PCR),and the resulting PCR products were subjected to Sanger direct sequencing.Results Among the 169 adolescent deaf patients,27(15.98％)patients had mutations in the SLC26A4 gene.This included 18(10.65％)patients with compound heterozygous mutation deafness and 9(5.33％)patients with the homozygous mutation.In addition,four new mutation sites were identified:c.197A＞C(p.K66T),c.688C＞A(p.Q230K),c.712delA(p.Ile238Leufs*51),and c.1649T＞G(p.F550C).A compound heterozygous mutation of c.919-2A＞G and c.712delA was identified in one of the children with an enlarged vestibular aqueduct.c.919-2A＞G was confirmed to be a pathogenic mutation site,while c.712delA was suspected to be a pathogenic mutation site.Based on this evidence,it is speculated that the compound heterozygous mutations of c.919-2A＞G and c.712delA are the underlying causes of deafness in this case.Conclusion SLC26A4 is indeed a commonly implicated gene in deafness cases in the Handan region.The mutations c.919-2A＞G and c.2168A＞G have been identified as the most frequent mutation sites associated with this gene.Interestingly,during Sanger sequencing,a novel mutation c.712delA in the SLC26A4 gene was found to be the cause of deafness in a child.
non-syndromic deafnessSanger direct sequencingSLC26A4genetic variation
NETL
NSTL
万方数据
