[Analysis the relationship between SLC26A4 mutation and current diagnosis of inner ear malformation in children with sensorineural hearing loss].

OBJECTIVE

Explore the relationship between the pathogenic mutations of SLC26A4 gene and inner ear malformation, and analyze the feasibility of genetic testing to help current diagnosis in part of children with sensorineural hearing loss.

METHOD

2094 cases of children were detected by SLC26A4 with the method of DNA sequence. CT phenotypes of those children were classified according to the method proposed by Sennaroglu. We analyzed the relationship between the pathogenic mutations of gene and the CT phenotypes.

RESULT

(1) 685 cases of inner ear malformations were found in 2094 cases of children with sensorineural hearing loss by CT examination (371 cases of cochlea malformation were consisted of the follow types of malformation. Michel deformity was 6 cases, cochlea aplasia was 8 cases, common cavity deformity was 12 cases, incomplete partition type I was 27 cases, cochlea hypoplasia was 30 cases and Mondini malformation was 288 cases); Vestibular aqueduct was 265 cases; Vestibular/semicircular canal/internal auditory canal were 49 cases, normal was 1409 cases. (2) The DNA sequence results revealed that 465 cases carried pathogenic mutations (Bi-allelic mutations) of SLC26A4 gene, among which 135 cases were homozygous, 330 cases were compound heterozygous. (3) Pathogenic mutations of SLC26A4 gene detected 100% (465/465) in the group related to vestibular aqueduct malformation.

CONCLUSION

The results suggest that pathogenic mutation of SLC26A4 gene is closely related to the CT phenotype of vestibular aqueduct malformation. Detecting of pathogenic mutations for hearing loss is binging the possibility to identify children with inner malformations at an early stage. As a consequence, it will improve the current diagnosis and therapeutical option.