BULL TERRIER HEREDITARY NEPHRITIS - A MODEL FOR AUTOSOMAL-DOMINANT ALPORT SYNDROME

Bull terrier hereditary nephritis is inherited as an autosomal dominan t disease and causes renal failure at variable ages in affected dogs. The aims of this study were to compare the clinical, ultrastructural a nd immunohistochemical features of bull terrier hereditary nephritis w ith the characteristics of the human forms of Alport syndrome. Many an imals with bull terrier hereditary nephritis have hematuria, and some have anterior lenticonus. However, deafness is not associated with the renal disease, and affected dogs do not have the large platelets that are occasionally seen in patients with autosomal Alport syndrome. The glomerular capillary basement membrane (GCBM) in affected bull terrie rs has an identical ultrastructural appearance to that seen in X-linke d Alport syndrome, with lamellations and intramembranous electron-dens e deposits. However, both the Goodpasture and the Alport antigens, whi ch represent parts of the alpha 3(IV) and alpha 5(IV) collagen chains, respectively, are present in the GCBM of affected dogs. Bull terrier hereditary nephritis represents an animal model for autosomal dominant Alport syndrome, and can be used to further examine how genetic mutat ions affect a basement membrane protein and the corresponding membrane structure.