Three novel mutations of STK11 gene in Chinese patients with Peutz-Jeghers syndrome

Background: Peutz-Jeghers syndrome (PJS) is a rare autosomal dominant inherited disorder characterized by gastrointestinal (GI) hamartomatous polyps, mucocutaneous hyperpigmentation, and an increased risk of cancer. Mutations in the serine-threonine kinase 11 gene (SKT11) are the major cause of PJS. Case presentation: Blood samples were collected from six PJS families including eight patients. Mutation screening of STK11 gene was performed in these six families by Sanger sequencing and multiplex ligation-dependent probe amplification (MLPA) assay. Three novel mutations (c.721G > C, c.645_726del82, and del(exon2-5)) and three recurrent mutations (c.752G > A, c.545 T > C and del(exon1)) in STK11 were detected in six Chinese PJS families. Genotype-phenotype correlations suggested that truncating mutations trend to result in severe complications. Conclusion: These findings broaden the mutation spectrum of the STK11 gene and would help clinicians and genetic counselors provide better clinical surveillance for PJS patients, especially for ones carrying truncating mutation.