[Familial adenomatous polyposis: early diagnosis by genetic mapping]

The use of probes detecting polymorphic loci within the human population has enabled accurate localization of the genetic defect responsible for familial adenomatous polyposis on chromosome 5. This was used to screen two families for the presymptomatic diagnosis in children of an affected parent. In both cases, the use of 8 polymorphic probes located on either side of the gene provided information which could be used in the management of children born from the patients at risk. The set of probes used in this work should be informative in most of the affected adenomatous polyposis families.