Clinical phenotype and pathogenic variation analysis of an autosomal dominant deafness family
10.3969/j.issn.1006-7299.2025.06.002
- VernacularTitle:一个常染色体显性遗传性聋家系的临床表型及致病变异分析
- Author:
Mengfei CAI
1
;
Ting ZHANG
;
Wanli HE
;
Mengli ZHANG
;
Xiaosai ZHANG
;
Hongen XU
;
Bei CHEN
Author Information
1. 郑州大学第一附属医院耳科(郑州 450052)
- Publication Type:Journal Article
- Keywords:
HOMER2 gene;
DFNA68;
Terminator codon mutation
- From:
Journal of Audiology and Speech Pathology
2025;33(6):520-524
- CountryChina
- Language:Chinese
-
Abstract:
Objectiv To investigate an autosomal dominant non-syndromic hearing loss family pedigree com-prehensively,aiming to precisely define its clinical phenotypes and uncover the underlying molecular genetic etiolo-gy.Methods A detailed interrogation of the proband's medical history and family history was conducted.Physical examinations,audiological assessments and temporal bone CT scans were performed.Genomic DNA was extracted from the peripheral blood of the proband(Ⅳ-8)for whole-exome sequencing(WES).Subsequently,candidate vari-ants identified through WES were validated among family members using Sanger sequencing.Results There were 36 individuals in 4 generations in this family pedigree,showing autosomal dominant inheritance.Among them,16 individuals presented with progressive hearing loss.Audiological examinations were completed for 13 of them,re-vealing normal hearing in three individuals(Ⅲ-1,Ⅲ-1 1,Ⅳ-4)and bilateral symmetric hearing loss of varying se-verity in the remaining ten(Ⅱ-2,Ⅱ-4,Ⅱ-10,Ⅲ-4,Ⅲ-10,Ⅲ-13,Ⅲ-14,Ⅳ-1,Ⅳ-7,Ⅳ-8),and the degree of hearing loss was related to age.WES of Ⅳ-8 revealed that she carried the variant NM_199330.2(HOMER2):c.1064 A>G(p.Ter354Trpext10),and Sanger sequencing verified the variation at this site.Peripheral blood samples of 18 individuals in this family were collected in total.All affected individuals(Ⅱ-2,Ⅱ-4,Ⅱ-10,Ⅲ-4,Ⅲ-9,Ⅲ-10,Ⅲ-13,Ⅲ-14,Ⅳ-1,Ⅳ-7,Ⅳ-8)carried the HOMER2 c.1064 A>G variant,except for one young member(Ⅳ-6)who had not yet developed hearing loss.Unaffected individuals(Ⅱ-5,Ⅲ-1,Ⅲ-5,Ⅲ-11,Ⅳ-2,Ⅳ-4)lacked the variant,demonstrating complete cosegregation of genotype and phenotype.According to ACMG guide-lines,this variant was classified as likely pathogenic(PM2+PP1+PM4).Conclusion The c.1064 A>G(p.Ter354Trpext10)variant of the HOMER2 gene is the molecular genetic etiology of this hereditary deafness family pedigree.