8A 3. Interpreting Data on cancer

Question 1

is there a single cause for cancer

Answer 1

no but there are lots of different ‘risk factors’

Question 2

what are risk factors

Answer 2

things that increase a persons chance of getting cancer

Question 3

risk factors can be ____ or ____

Answer 3

environmental

genetic

Question 4

genetic risk factors explained

Answer 4

some cancers linked with specific inherited alleles

inherit allele = more likely to get that type of cancer

Question 5

environmental risk factors explained

Answer 5

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

Question 6

why is it difficult to interpret the relative contributions of genes and environment

Answer 6

some characteristics can be affected by many different genes (they’re polygenic) and many environmental factors
difficult to know which factors (genes or environment) having greatest effect
hard to draw conclusions about causes of variation

Question 7

how understanding role of proto-oncogenes and tumour suppressor genes is helpful in coming up with ways to prevent cancer

Answer 7

1. specific cancer-causing mutation known- can screen for mutation in a persons DNA
2. preventative steps can be taken (reduces risk)
   mastectomy (removal of breasts)
   screened for signs of breast cancer more often (early diagnosis increases chance of recovery)
3. more sensitive tests can be developed which can lea to earlier more accurate diagnosis

Question 8

example of a gene with a mutated allele that increases chance of developing breast cancer

Answer 8

BBCA1 tumour supressor gene

Question 9

how understanding role of proto-oncogenes and tumour suppressor genes is helpful in coming up with ways to treat and cure cancer

Answer 9

1. treatment different for different mutations. knowing specific mutations can be useful for developing drugs to effectively target them.
2. some mutations require more aggressive treatment. understanding how mutation works can help produce best treatment plan e.g. more aggressive= higher doses of radiotherapy
3. gene therapy (faulty alleles replaced by working versions)