Genetics of Cancer Flashcards
Is all cancer genetic?
yes, but not all is hereditary.
Is most cancer hereditary?
no, most is sporadic
What are features of sporadic cancer?
majority of cancer, not usually inherited, diagnosis later in life.
What are features of familial cancer?
tow ore more affected closely related fan members, later onset, unilateral, unclear pattern of inheritance.
What are features of inherited cancers?
5-10% of cancers
early onset
bilateral or multifocal
clear inheritance pattern.
What are factors that affect is someone with an altered gene gets cancer?
- modififer genes
- carcinogens
- response to DNA damage
- hormonal/reproductive factors
With oncogenes, how many mutations are sufficient for development of cancer?
one
With tumor suppressor genes, how many mutations are sufficient for development of cancer?
2
Is breast or ovarian cancer mostly hereditary?
no mostly sporadic.
What is the genes associated with breast cancer?
BRAC1, chormosome 17, auto D
BRAC2, chomrosome 13, Auto D
What is a unique feature to look for in someone who has FAP?
CHRPE–> pigmented area on the retina.
If FAP goes untreated, what is the likelihood they will develop cancer?
100%
What gene is associated with FAP?
APC on chromo 5q
what is a variant of FAP?
Gardner’s syndrome.
What are the Amsterdam criteria for HNPCC?
3-2-1 rule
3 or more relatives with verified CRC
2 or more generations
1 case of first degree relative, 1 CRC by age 50
failure to meet criteria does NOT exclude HNPCC from diagnosis