Autosomal Recessive Nonsyndromal Profound Childhood Deafness in a Large Pedigree: Audiometric Features of the Affected Persons and the Obligate Carriers

Familial mondini dysplasia

“…Her audiometric findings are similar to those observed in heterozygous females carrying genes for X‐linked diseases with deafness 13 . Similar audiometric profiles were described in two previous reports involving parents of children with autosomal recessive profound hearing loss, although the authors of both studies concluded that these profiles were not sufficiently significant to predict heterozygous carrier status 14,15 . However, the lack of another identifiable etiology for the mother's hearing loss supports the hypothesis that it may represent a heterozygous carrier phenotype.…”

“…Although the father must also be a carrier if inheritance is recessive, he does not appear to have a heterozygous carrier phenotype. This is not unexpected because only 30% of the parents in the study of Anderson and Wedenberg 16 and 50% of the obligate carriers in the study by Marres and Cremers 15 had abnormal audiometric thresholds. Variable expressivity of the heterozygous phenotype could be the result of differing mutations in the same gene, as well as modifying genetic and environmental factors.…”