Genetic predisposition to cancer Flashcards Preview

Principles of disease JK > Genetic predisposition to cancer > Flashcards

Flashcards in Genetic predisposition to cancer Deck (15)
Loading flashcards...
1
Q

What is Cancer?

A

A common disease of somatic cells that are mostly due to chance and most are non-inheritable although increased chance with genetic predisposition

2
Q

Oncogenes

A

1 mutation is sufficient for cancer and accelerates cell division
Protooncogene ==> Oncogene
Eg Thyroid cancer or by a virus

3
Q

Tumour suppressor genes

A

1 mutation already in carrier eg BRCA1/2
Cells breaks which inhibit cell cycle and promote apoptosis
2 hit hypothesis

4
Q

DNA damage response genes

A

Repair DNA and both genes fail = CANCER

Eg colon cancer

5
Q

Base pair mismatch

A

Either have normal repair or defective repair (MMR+) which leads to MSI

6
Q

Microsatellite instability

A

Addition of nucleotide repeats

7
Q

Other causes of cancer include

A

Autosomal recessive syndrome

Multiple modifier genes which explains families with history but no mutation

8
Q

De Novo Mutation

A

Mutation occurs newly in germ cell of parent

9
Q

Most cancer susceptibility genes are…

A

Dominant with incomplete penetrance

10
Q

Risks for breast cancer

A

Age, alcohol, diet, late menopause, no children, oestrogen use

11
Q

BRCA 1

A

Checkpoint mediator for DNA damage signal and repair which remodels chromatin

12
Q

Risks for colorectal cancer

A

Age, high fat, low fibre, IBS

13
Q

How to manage cancer risk in Adenomatous polyposis syndrome

A

Surveillance, surgery, chemoprevention eg steroids

14
Q

Predictive gene testing

A

Test relatives, surveillance, only test at adulthood and gene variant problems

15
Q

Do polymorphisms cause disease?

A

NO - the wrong message does