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Neuro-rehabilitation Approach for Sudden Sensorineural Hearing Loss
09:44

Neuro-rehabilitation Approach for Sudden Sensorineural Hearing Loss

Published on: January 25, 2016

[Propionic acidemia and sensorineural hearing loss: is there a connection at the molecular genetics level?]

S Brosch1, A Rauffeisen, M Baur

  • 1Sektion für Phoniatrie und Pädaudiologie der Universitäts- Hals-, Nasen-, Ohrenklinik, Schillerstr. 15, 89077, Ulm, Deutschland. sibylle.brosch@uniklinik-ulm.de

HNO
|April 7, 2007
PubMed

Insights

Propionic acidemia, a genetic disorder, involves propionyl-CoA carboxylase (PCC) enzyme defects. While deafness is observed in patients, this study found no direct link between PCC gene mutations and severe sensorineural hearing loss.

Area of Science:

  • Genetics
  • Metabolic Disorders
  • Audiology

Background:

  • Propionic acidemia results from genetic defects in propionyl-CoA carboxylase (PCC), leading to toxic propionic acid accumulation.
  • An increased incidence of deafness is noted in propionic acidemia patients, prompting investigation into a potential genetic link.

Purpose of the Study:

  • To investigate whether mutations causing propionic acidemia are also responsible for genetic deafness.
  • To explore the relationship between PCC gene mutations and hearing loss in affected families.

Main Methods:

  • Pure tone audiometry was performed.
  • Pedigrees were analyzed, and DNA was isolated from families with propionic acidemia.
  • Genetic analysis focused on PCCA and PCCB subunits.

Main Results:

  • One family exhibited mutations in both PCCA and PCCB subunits.
  • Only one affected female in this family displayed the complete phenotype.
  • A novel mutation in the PCCB subunit (p.R113X) was identified.

Conclusions:

  • The identified PCCB subunit mutation (p.R113X) is novel.
  • No correlation was found between the studied mutations and severe sensorineural hearing loss.
Abstract

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