Pathogenic Gene Mutation Analysis For A Chinese Pedigree With Peutz-Jeghers Syndrome

Objective: To detect the pathogenic gene?STK11? in a Chinese family with Peutz-Jeghers syndrome?PJS?, hoping to find the location of the STK11 gene mutation.Methods:?1? A detailed clinical examination was performed for a patient with PJS and for his family members at the dermatology department of Wuhan Union hospital.Seven people took part in this study, including three patients and four normal controls.?2? 5ml of peripheral venous blood was collected from every member of the PJS affected family to extract the genomic DNA by SDS-lysis method?3? Amplification of all exons and sequences of connected region between exons and intron in the STK11 gene was done by polymerase chain reaction?4?PCR amplified fragments were sequenced to find the location of the gene mutation by Sanger method.?5? In order to validate the causative mutation within the family, we applied the DNA fragments of the mutation location in other patients and normal family members and sequenced the products by Sanger method.Results:?1? Sequencing showed that the pathogenic site is c.642₆44del G?p.Gln214 fs X286? of the fifth exon in the STK11 gene of the proband.?2? Pedigree analysis found that the proband's daughter had the same mutation, and no abnormalities were found at this site in his father or other family members.Conclusion: From this study we found that the proband and his daughter had a frameshift mutation at c.642₆44del G?p.Gln214 fs X286? of the fifth exon in the STK11 gene.The mutation may be the molecular basis of pathogenesis in PJS patients in this family.This mutation is a known mutation reported in 2005.