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Flashcards in genetic predisposition to cancer Deck (22)
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1

genetic processes associated with cancer

-the activation of oncogenes
-the deactivation of tumour suppressor genes
-the abnormal working of of DNA damage-response genes

2

proto-oncogene

normal gene that codes for proteins to rgeulate cell growth and differentiation

3

what changes a proto-oncogene into an oncogene?

mutation

4

how many 'hits' are required for oncogenes to cause cancer

only one mutation in the gene on one chromosome is required

5

how many 'hits' are required for tumour supressor genes to cause cancer?

2 mutations are required, one in each of the genes on each chromosome

6

what are DNA damage-response genes?

The repair mechanics for DNA

7

how many 'hits' are required to cause cancers due to DNA damage-response genes ?

two hits are required, one in each copy of the gene, this speeds the accumulation of other mutations in critical areas

8

what is miss match repair?

occurs when there is a base pair miss match, eg. T is paired with C in DNA replication. Repair mechanisms are used to fix this abnormality.

9

what happens if there is defective miss match repair mechanisms?

risk of cancer forming

10

what can microsatellite instability tell us?

that there is a problem with miss match repair

11

dysplastic tumour

A tumour that is benign but could progress to malignancy

12

example of oncogene

RET

13

example of tumour supressor gene

-BRCA1 and BRCA 2
-RB

14

what does a loss of function in BRCA 1 or BRCA2 cause?

breast cancer

15

what does a loss of function in RB gene cause?

retinoblastoma

16

what does activation of the RET gene cause?

MEN2 multiple endocrine neoplasia

17

examples of DNA repair genes and what do they cause?

MLH1, MSH2, MSH6, PMS1, PMS2
hereditary non-polyposis colon cancer

18

what is a de novo mutation?

a mutation that occurs in germ cell of a parent, there is no family history of the cancer syndrome

19

main risk factors foe breast cancer

-ageing
-family history
-dietary factors eg. alcohol
-lack of excersise

20

example of autosomal recessive syndromes

MYH polyposis

21

risk factors for colorectal cancer

-ageing
-personal history of colorectal cancer or adenomas
-high fat, low-fibre diet
-inflammatory bowel disease
-family history of CRC

22

what is predictive gene testing?

test carried out to determine a patient's risk of developing a cancer