Lectures 1/2 Flashcards
What is cancer?
Cancer is a condition where abnormal cells grow and reproduce uncontrollably.
What evidence is there for cancer being genetic?
-most carcinogens are also mutagens
-no mini epidemics so not contagious
-incidence increase with age in correlation with DNA damage
-chromosome instability a common feature
-defects in DNA repair increase probability of cancer
What are the two types of mutation?
Somatic and Germ line
What are germ-line mutations?
-mutations in every cell in the body
-passed directly from parent to child
-less common than somatic
-called inherited cancer
What are somatic mutations?
-known as acquired mutations
-occur due to damages to genes during a persons lifetime
-aren’t passed from parent to child
-most common cause of cancer
-called sporadic cancer
What are cancer genes?
Genes that before mutation have a normal function but once mutated can cause cancer
What are the two main groups of cancer genes?
Oncogenes and Tumor suppressor genes
What is the normal version of oncogenes?
Proto-oncogenes
Are oncogenes dominant or recessive?
Tend to be dominant acting
Can mutations in oncogenes be inherited?
Not usually
Do Timor suppressor genes act recessively or dominantly?
Recessive acting
Can tumor suppressor genes mutations be inherited?
Can be inherited in family cancer syndromes
What are the usual function of Timor suppressor genes?
Usually prevent cell growth/division
What happens when a tumor suppressor gene mutates?
You get a loss of function
Example of an inherited tumor suppressor gene cancer?
Retinoblastoma