Basics
- Genes which normally control the cell cycle
- Exhibit a recessive effect - both copies must be mutated before cancer occurs
Examples
- P53
- APC: colorectal cancer
- NF-1: neurofibromatosis
- RB: retinoblastoma
P53 Gene
- This is a tumour suppressor gene located on chromosome 17p. It is the most commonly mutated gene in breast, colon and lung cancer
- P53 is thought to play a crucial role in the cell cycle, preventing entry into the S phase until DNA has been checked and repaired. It may also be a key regulator of apoptosis
Li-Fraumeni Syndrome
- This is a rare autosomal dominant disorder characterized by the early onset of a variety of cancers such as sarcomas and breast cancer.
- It is caused by mutation in the p53 gene