STK11 is a ‘cancer protection’ gene that helps to protect against cancer of the gastrointestinal tract, pancreas, breast, cervix and ovary.
Everyone has two STK11 genes (one from their mother, and one from their father). If one of the genes is not working, this is known as having a faulty STK11 gene, or having an STK11 mutation. People with a faulty STK11 gene are known to have Peutz-Jeghers syndrome.