A prospective biological study in relation to a family with Li-Fraumeni syndrome

Abstract

The Li-Fraumeni syndrome (LFS) is an autosomal dominant hereditary disorder associated with different tumor types in childhood and young adults. Approximately 70% of LFS cases contain germline mutations in the TP53 gene. We report a case of a family suspected of LFS. The proband and four members of the family affected were diagnosed with cancer at an early age and they all died except the proband. Exons 5-9 from TP53 gene were analysed by direct amplification and sequencing in 7 family members. The analysis revealed a germline nonsense mutation in exon 8 at codon 306 of the codified region of the TP53 gene, causing a change of CGA to TGA (Arg→Stop) in the proband, her mother, her cousin and her maternal uncle. Proband's maternal grandmother and aunt do not have the mutation. The members of this family that were studied meet the criteria of classic LFS and the described mutation increases their susceptibility to develop cancer. The proband's maternal grandfather died of lung cancer in 1993, and we believe that he was the carrier of the mutation in this family.