Comparative effects of germfree and ambient environments on the development of cystic kidney disease in CFWwd mice.

A spontaneously occurring murine renal cystic disease that resembles human adult-onset polycystic renal disease is described. The disease that develops in CFWwd mice is characterized by multiple bilateral cysts in the kidneys in all affected animals and hepatic cysts in approximately 20% of these animals with disease. Occasional thoracic aortic aneurysms were also observed in animals with cystic disease. The prevalence of the disease appears to be determined by the degree of exposure to the ambient environment. A germfree colony of CFWwd mice only rarely displayed the disease, whereas virtually 100% of animals housed for their entire life in the ambient environment died with the disease. Germfree mice removed from the axenic environment and placed in the ambient environment developed the disease, but at a lower prevalence than those animals born and reared in the ambient environment. Disease prevalence in animals reared in environmentally protected caging was between that in germfree and conventional animals. Genetic studies of AKR mice indicated that the disease is inherited in an autosomal dominant fashion but with reduced penetrance.