Analysis of a pedigree of Peutz-Jeghers syndrome and RET proto-oncogene mutation: one case report and literature review

Peutz-Jeghers syndrome (PJS) is a rare autosomal dominant inherited disorder characterised by gastrointestinal (GI) hamartomatous polyposis and mucocutaneous pigmentations. PJS is associated with an increased cancer risk, including GI and various extra-GI malignancies. In this study, we tracked this family for 8 years, and analyzed the clinical data of the PJS pedigree including two generations. In our research, the studied family members, including the proband, older daughter and younger daughter, all detected to have three heterozygous mutations in the RET gene that were inherited from the proband. The existed three mutant spots included exon 5 (GTG>ATG, Val292Met), exon 2 (CGC>CAC, Arg67His) and exon 18 (CGC>TGC, Arg982Cys) in RET. Our study provides an observation of the genetic heterogeneity of PJS. This pedigree investigation showed that it is critical to establish a long-term follow-up system for PJS patients and their families.