Liver kinase B1 (LKB1, also known as STK11) was first identified as the causal mutation in Peutz–Jeghers Syndrome (PJS), a rare inherited autosomal dominant disorder characterised by the development of benign gastrointestinal hamartomas and the early onset of cancer (Hemminki et al, 1998). The gene discussed is STK11; the disease is cancer.