The tumor suppressor serine-threonine kinase LKB1, also referred to as STK11, is responsible for Peutz-Jeghers Syndrome (PJS), an autosomal-dominant disorder characterized by mucocutaneous hyper-pigmentation and benign gastrointestinal hamartomatous polyps and is attributed to mutations in LKB1 [1]. The gene discussed is STK11; the disease is Peutz-Jeghers syndrome.