[Study of hereditary fructose intolerance by methods of molecular biology].

Fructose intolerance is caused by a deficit of the liver aldolase B enzyme. Its molecular mechanisms were studied at different sites: The protein was studied by a method combining electrophoresis, transfer and immunology. It was present in the 15 cases examined. The genetic variability was demonstrated by the quantitative differences of the immunoreactive proteins. Aldolase messenger RNA was prepared and used to direct in vitro synthesis of human aldolase. Cloning complementary DNA of human aldolase was achieved by using the messenger RNA. Two clones were prepared. The aldolase B gene was then analysed using restriction enzymes in 60 control subjects and 11 patients. An abnormality of the DNA was demonstrated in one of the patients and in her father.