[Pre-symptomatic diagnosis of Huntington disease by polymerase chain reaction].

The authors are reporting on the presymptomatic diagnosis of the autosomal dominant Huntington's disease applying the polymerase chain reaction for the first time in Hungary. The detection of the products yielded by polymerase chain reaction was carried out by silver stained polyacrylamide gel. This silver staining gave appropriate result without using radioactive technique. Cause of the disease is the greater number of CAG repeat sequence in the region of the Huntington's disease gene. The number of CAG repeats in Huntington patients is more than 37, while in not affected persons it is less than 34. Four members of two families each were examined and presymptomatic diagnoses were performed in two cases of both families. Normal alleles were detected in all cases. The tests supported the diagnoses of these patients suffering of clinically proved Huntington's disease.