[Creutzfeldt-Jakob disease in France. Value of familial forms. Is there a gene controlling the length of the incubation period?].

An extensive search for patients who died of Creutzfeld-Jakob disease in France between 1968 and 1982 resulted in the discovery of 327 cases, 233 of which were histologically proven and 29 transmitted to animals; 17 patients belonged to 6 families. Further investigations among members of these 6 families yielded 21 additional cases, i.e. a total of 38 familial cases. Studies among sibships suggested an autosomal dominant pattern of transmission but did not exclude lateral contamination infancy. The patients' age at death was 10 to 15 years lower than that of the total of French cases and seemed to be a characteristic of each individual family. This suggests that, as in scrapie, a gene may control the length of the incubation period.