Topic 8—A: Mutations and gene expression- 4. Interpreting data on cancer

Question 1

What can risk factors either be?

Answer 1

• genetic
• environmental

Question 2

Genetic factors

Answer 2

• some cancers are linked with specific inherited alleles
• if you inherit that allele you’re more likely to get that type of cancer
  E.g. hereditary mutations of the gene BRCA1 can greatly increase the chance of a woman developing breast cancer in her lifetime

Question 3

Environmental factors

Answer 3

• exposure to radiation, lifestyle choices such as smoking, increased alcohol consumption and a high fat diet have all been linked to an increased chance of developing some cancers

Question 4

What is cancer caused by?

Answer 4

• mutations in proto-oncogenes and tumour suppressor genes

Question 5

Preventing cancer

Answer 5

• if a specific cancer-causing mutation is known then it it possible to screen for the mutation in a persons dna
• knowing about this increased risk means that preventative steps can be taken to reduce it
• knowing about specific mutations also means that more sensitive tests can be developed, which can lead to earlier and more accurate diagnoses

Question 6

Treating and curing cancer

Answer 6

• the treatment for cancer can be different for different mutations so knowing how specific mutations actually cause cancer can be very useful for developing drugs to effectively target them
• some cancer causing mutations require more aggressive treatment than others so understanding how the mutation that causes them works can help produce the best treatment plan
• gene therapy (where faulty alleles in a persons cells are replaced by working versions of those alleles may also be able to treat cancer caused by some mutations