Clinical Cancer Genetics Flashcards
What is the difference between a hereditary and acquired mutation?
Hereditary = germline Acquired = any other time
What are the two different types of genetic susceptibility?
High risk cancer genes
Familial cancer
What are high risk cancer genes?
Single mutation in one high-risk gene
What are familial cancers?
Multiple lower risk genetic factors
What is an example of a high effect common variant influencing common disease?
Macular degeneration
What do the most common high risk cancer predisposition genes code for?
Retinoblastoma
Medullary thyroid
What can you use to identify genetically predisposed cancers?
Family history
Syndromic features
Tumour testing
Pathology of cancer
What does a family history assessment show?
Age of onset and type of cancer
How do you get a polygenic risk score?
GWAS for cancer associated SNPs
What are the syndromic features of cancer predisposition genes?
Trichilemmoma
Mucocutaneous pigmentation
How can you check if a mutation is germline?
blood test
What is stratified prevention?
Categorisation of the population into risk groups, each of which would be offered a different intervention
How often are all women screened for breast cancer?
3 yearly from 47-70
How big of a risk is B1 surveillance?
Medium
How big of a risk is B2 surveillance
High
If you are on B1 surveillance how often do you get invited for breast cancer screening?
Anually 40-50
3 yearly 50-70
How often do you get invited for breast cancer screening if you’re on B2 surveillance?
Annual 40-60
3 yearly 60-70
What is chemo prevention?
Use of drugs to preemptively minimise cancer risk
At what % likelihood do you test for high risk cancer genes?
10%
What type of gene are most cancer predisposition genes?
Autosomal dominant
Why has there been a move to WGS for genetic cancer testing?
Increased mutation detection
Increased understanding of mutagenesis
Greater understanding of phenotypic spectrum/cancer risk
What are the possible outcomes of diagnostic genetic testing?
No disease causing variant
Variant of uncertain sigificance identified
Disease causing variant identified
If you identify a pathogenic variant, how can you manage it?
Risk reducing surgeries
Chemoprevention
Invasive and non-invasive imaging
What is predictive testing?
A test in a well person to predict future risk
What are the BRCA1 and BRCA2 genes involved in?
DNA repair and regulation of transcription
What is the prevelance of lynch syndrome?
1 in 440
What genes are involved in lynch syndrome?
MLH1, MSH2, MSH6 and PMS2
What types of cancer is lynch syndrome most associated with?
Colorectal, endometrial and ovarian
What risk reducing surgery is done in lynch syndrome?
Hysterectomy
What chemoprevention is done in lynch syndrome?
Low dose aspirin
