Doberman Pinscher dogs suffering from congenital deafness and dysfunction of the vestibular system have been first described in 1992. However, until recently, the cause of the described disease has been unknown. A mutation in the PTPRQ gene now has been found to be associated with deafness and vestibular dysfunction in this breed. The disease is inherited in an autosomal recessive manner. Affected pups are deaf by 3 weeks of age and show signs of vestibular disease like head tilt, circling and ataxia. In the inner ear, progressive cochlear degeneration with a loss of auditory sensory cells has been described. Moreover, abnormal or absent otoconia could be found in the vestibular system of some affected dogs without sensory cell loss.
1-2 weeks after arrival of the sample in the lab