Tumour suppressor genes

Tumour suppressor genes normally act to inhibit cell
proliferation by stopping cell division, initiating apoptosis (cell
death) or being involved in DNA repair mechanisms. Loss of
function or inactivation of these genes is associated with
tumorigenesis. At the cellular level these genes act in a
recessive fashion, as loss of activity of both copies of the gene is
required for malignancy to develop. Mutations inactivating
various tumour suppressor genes are found in both sporadic
and hereditary cancers.