Cancer Genetics

Question 1

What is cancer?

Answer 1

Condition where cells in a specific part of the body grow and divide uncontrollably

Can begin in one part of the body and spread ( metastasis)

Question 2

How does cancer start?

Answer 2

With mutations

Question 3

What are acquired mutations?

Answer 3

Arise during an individuals lifetime due to environmental impacts or age

Mutation in cells in one part of the body leads to unregulated cell division and the formation of a tumour

‘spontaneous’ cancer

Question 4

What are Germline mutations?

Answer 4

Inherited mutations from either sperm or egg

Mutant Allele is present in all the cells in the body

‘hereditary’ cancer

Question 5

What is an oncogene?

Answer 5

Mutated genes that have the potential to cause cancer

Before they are mutated they are called proto-oncogenes, and play a role in normal cell division

Positive regulator genes. Mutations are typically dominant acting. Mutation in one copy of the gene leads to activation

Question 6

What are tumour suppressor genes?

Answer 6

Limit how much a cell can grow
Control how fast a cell divides
Fixes mistakes in DNA
Controling when a cell divides

Inhibit cancerous processes. Mutations tend to be recessive acting. Cancer develops if a carried individual requires a deleterious somatic mutation in the same tumour suppressor gene and consequently have a cell with no functional copies of that gene

Question 7

How can cancer result?

Answer 7

Oncogenes activated OR tumour suppressor genes inactivated