OBJECTIVETo screen for potential mutations of LKB1 gene in Chinese familial Peutz-Jeghers syndrome (PJS) patients and analyze their clinical manifestations.

METHODSEleven PJS families were collected and genomic DNA of peripheral blood was extracted. Typically mucosal pigmentation and hamartomatous polyps were present in all 11 probands. Mutation screening of the probands were carried out by PCR and direct sequencing. Two hundred and fifty healthy adults were enrolled as normal controls, for whom genomic DNA of peripheral blood was also extracted. PCR-denaturing high performance liquid chromatography was carried out to verify the mutation identified in the patients.

RESULTSNine germline mutations were identified in eight PJS patients, which included 7 point mutations, 1 deletion and 1 insertion. Among these, 4 were considered to be pathogenic, of which 2 were de novel, 4 were considered to be polymorphism, and 1 was uncertain.

CONCLUSIONLKB1 gene mutations with pathogenic effect are a common cause of familial PJS in Chinese patients. Most mutations are point mutations.