Exonic STK11 deletions are not a rare cause of Peutz-Jeghers syndrome

Background: Peutz-Jeghers syndrome (PJS) is a rare, autosomal dominant cancer predisposition syndrome characterised by oro-facial pigmentation and hamartomatous polyposis of the gastrointestinal tract. A causal germline mutation in STK11 can be identified in 30% to 80% of PJS patients. Methods: Here we report the comprehensive mutational analysis of STK11 in 38 PJS probands applying conventional PCR based mutation detection methods and the recently introduced MLPA ( multiplex ligation dependent probe amplification) technique developed for the identification of exonic deletions/duplications. Results: Nineteen of 38 probands (50%) had detectable point mutations or small scale deletions/insertions and six probands (16%) had genomic deletions encompassing one or more STK11 exons. Conclusions: These findings demonstrate that exonic STK11 deletions are a common cause of PJS and provide a strong rationale for conducting a primary screen for such mutations in patients.