Cancer and Genetics Flashcards
What is a germ line mutation (3)
A mutation that is inherited
Normally dominant gene condition
Makes minority of inherited cancers
What is a somatic mutation (2)
A mutation that occurs during cell division - Not inherited
Makes majority of inherited cancers
Cancer is a disease of
Mosaicism largely caused by post-zygotic mutations
Factors that promote cancer cells from proliferating, invading and metastasis (3)
DNA damage/instability
Growth factors
Oncogenes
Factors that inhibit cancer cells from proliferating, invading and metastasis (2)
DNA repair
Tumour suppressors
Sequencing a cancer allows you to find what mutation types (2)
Driver mutations - Mutations that drive carcinogenesis
Passenger mutations - Incidental mutations that happen because the tumour is unstable (Don’t matter to cancer behaviour or drive)
2 hit hypothesis mechanism
Either occurs from inherited mutation with acquired (somatic) mutation or 2 acquried mutations
Common example of 2 hit hypothesis
Retinoblastoma
Mechanisms of gene activating (3)
Gene duplication
Gene promoter activation
Amino acid sequence change - Active protein configuration
BRCA1 mutation points (4)
Makes small part of familial breast cancer
Mutation carriers have 80% lifetime risk breast or ovarian cancer
Involved in DNA strand repair
It is an autosomal dominant gene
What is a polymorphism
Any variation in human genome that does not cause a disease in its own right bu it may predispose to a common disease
Breast cancer management (3)
Screening - Mammography
Hormonal manipulation - Tamoxifen
Surgical - Mastectomy
Mendelian disorders key point
High penetrance WITH low mutation/Polymorphism frequency
Common disorder key point
High mutation/polymorphism frequency with low penetrance
