Peutz-Jeghers syndrome

Peutz_Jeghers Syndrome (PJS, OMIM 175200) is a rare autosomal dominant disorder characterized by intestinal hamartomatous polyps, mucocutaneous melanotic pigmentation and predisposition to malignancies. The incidence rate of the disease ranges from 1 in 8,300 to 1 in 200,000 (Boardman,2002; Launonen,2005; Chae and Jeon,2014). Around 55% of affected patients show a family history of the disease. The clinical diagnosis of PJS can be confirmed by molecular genetic testing of STK11 (LKB1) in 80%-94% of affected individuals (Jenne et al.,1998; Hemminki et al.,1998).STK11 gene encodes a tumor suppressor serine/threonine-protein kinase involved in various processes such as cell metabolism, cell polarity, apoptosis and DNA damage response. A genotype-phenotype correlation between STK11 germline mutations and disease manifestations (e.g., the number of polyps, pigmentation pattern, cancer risk) is been proposed (Hemminki et al.,1998; Davidson,2007). Genetic heterogeneity is suggested by several patients negative at the mutational screening of STK11 gene and multiple causative loci described to date (Alhopuro et al.,2008; Bali et al.,1995; Markie et al.,1996; Mehenni et al.,1997; Schumacher et al.,2005; Wang et al.,2014)