Prevalence and formation of primary cataracts and persistent hyperplastic tunica vasculosa lentis in the German Pinscher population in Germany

Objective The objective of this study was to describe the prevalences of primary noncongenital cataracts (CAT) and persistent hyperplastic tunica vasculosa lentis (PHTVL) in the German Pinscher population in Germany and to analyze the mode of inheritance of CAT in this dog breed. Animals studied All German Pinschers with a certified veterinary ophthalmological diagnosis and born between 1993 and 2010 were included in this study. Examinations were performed between 1997 and 2013 by certified veterinary ophthalmologists of the German panel of the European Eye Scheme for Diagnosis of Inherited Eye Diseases in Animals (DOK). Procedures Data were reviewed retrospectively for the prevalence of PHTVL, and the prevalence, location and age at diagnosis of CAT. Inheritance of CAT was analyzed using the Singles Method. Results A total of 779 eye examination reports of 409 dogs were available. Primary noncongenital cataracts were diagnosed in 64 (15.6%), and PHTVL in 13 (3.2%) of the examined dogs. The pedigrees included 168 ophthalmologically examined dogs with 104 CAT-unaffected and 64 CAT-affected dogs. All affected animals were offspring of a frequently used stud-dog or closely related ancestors of this stud-dog. Simple segregation analysis revealed a recessive mode of inheritance for CAT. Conclusions An early onset form of CAT with various cortical, posterior polar or multiple locations was the most prevalent manifestation among close relatives in German Pinschers. The pedigree analysis indicated a hereditary component of cataract formation with a monogenic autosomal recessive pattern of inheritance.