Diagnosis; Mutation Confirmation

Sensorineural hearing loss affects 1-2/1000 live newborns; 50% is from genetic origin, 70% corresponding to autosomal recessive non-syndromic symptoms . Half of them have pathogenic variants in GJB2 gene (Connexin 26). In some patients where one or none has been found variants in GJB2 gene, a 342-kb deletion in the … Sensorineural hearing loss affects 1-2/1000 live newborns; 50% is from genetic origin, 70% corresponding to autosomal recessive non-syndromic symptoms . Half of them have pathogenic variants in GJB2 gene (Connexin 26). In some patients where one or none has been found variants in GJB2 gene, a 342-kb deletion in the GJB6 gene (Conexin 30) is observed. View more

Establish or confirm diagnosis

Tests performed
Entire test performed in-house

29 patients with severe non-syndromic sensorineural hearing loss with autosomal recessive hereditary pattern were studied. The coding region of the GJB2 gene was studied by sequencing and deletion of the GJB6 gene by PCR. 38% of patients presented variants in both alleles, 3% in a single allele and 59% no … 29 patients with severe non-syndromic sensorineural hearing loss with autosomal recessive hereditary pattern were studied. The coding region of the GJB2 gene was studied by sequencing and deletion of the GJB6 gene by PCR. 38% of patients presented variants in both alleles, 3% in a single allele and 59% no variants were found, but in these, benign variants were observed, which validates the sequencing study. Sanger sequencing analysis approaches an analytical sensitivity of almost 100%. View more

Is proficiency testing performed for this test? Help
Yes

Method used for proficiency testing: Help
Formal PT program

PT Provider: Help
American College of Medical Genetics / College of American Pathologists, ACMG/CAP