LACK OF GERM-LINE MUTATIONS IN THE P53 GENE EXON-4 TO EXON-8 IN PATIENTS WITH LATE-ONSET 2ND MALIGNANT NEOPLASMS

Previous studies have shown p53 germ-line mutations in some familial c ancer aggregations with or without the Li-Fraumeni syndrome (LFS). Suc h mutations were also reported in children and young adults with secon d malignant neoplasms (SMN). This led us to screen for p53 germ-line m utations in a group of seven patients affected with SMN, but character ized by an older age of onset than in the previous reports. No mutatio n was found in exons 4 to 8 and their boundaries using the single-stra nd conformation polymorphism technique. Our results give strong eviden ce for genetic heterogeneity of SMN, probably related to the age of ca ncer onset.