MS1; CANCER GENETICS TEST
QUESTIONS AND ANSWERS
What are the general causes of cancer? - ANSWER 1) Genetics
2) Hereditary factors
3) Environmental aspect
What are the 5 major types of tumors? What type of tissue do they
affect? - ANSWER 1) Carcinomas: epithelial tissue
2) Sarcoma: CT
3) Leukemias: hematopoietic organs
4) Lymphomas: lymphatics
5) Gliomas: CNS
Is cancer a disease? - ANSWER -no, predisposition
What is Knudson's Two-Hit model? What is an example? What are the 2
types and how do they occur? - ANSWER -states you need two
mutations for cancer
ex.) Retinoblastoma: AD with incomplete penetrance
1) Bilateral runs in family
-one copy bad already from inheritance
-second copy is sporadic mutation
2) Unilateral:
-1st copy appears sporadically via mutation
-second copy is sporadic also sporadic
What are oncogenes? Where do they come from? What genotype is
associated? - ANSWER -result from gain of function mutation of growth
promoting genes
-the normal gene is called proto-oncogene
-usually dominant mutation
, What are mutations that occur in tumor suppressor genes? What is
affected? What genotype is associated? - ANSWER -loss of function to
inhibit the growth inhibiting activates
-need to be recessive
What are the DNA repair genes? What is their function? - ANSWER def:
help maintain integrity of the genome
-BRCA1, BRCA2, Mismatch (MLH and MSH)
How does the cell cycle work? What are the factors? What are they
regulated by? What are checkpoints and which is important for cancers?
- ANSWER -use cyclins and cyclin dependent kinases
-regulation done via phosphorylation and CDK inhibitors
-checkpoints: G1/S (important for cancer), S/G2, G2/M. G0
What are the function of the following in the cell cycle:
1) Rb
2) p53
3) p16
4) p21 - ANSWER 1) Rb blocks E2F
-G1-S phase checkpoint
2) p53:
-activate p21
-halt DNA rep
3) p16:
-block Cyclin D1/CDK4/6 from phosphorylating Rb
4) p21:
-inhibit Cyclin E from binding CDK2
How do you find cancer genes? - ANSWER -lost cell markers indicated
loss of heterozygosity (LOH) near gene of interest
What is GWAS? What is it used for? What techniques are used? What
can be screened? What is used to reduce burden? - ANSWER -GWAS:
genome wide association studies
-many markers screened in one test
-used microarrays or WGS
-can screen many markers such as SNPs
QUESTIONS AND ANSWERS
What are the general causes of cancer? - ANSWER 1) Genetics
2) Hereditary factors
3) Environmental aspect
What are the 5 major types of tumors? What type of tissue do they
affect? - ANSWER 1) Carcinomas: epithelial tissue
2) Sarcoma: CT
3) Leukemias: hematopoietic organs
4) Lymphomas: lymphatics
5) Gliomas: CNS
Is cancer a disease? - ANSWER -no, predisposition
What is Knudson's Two-Hit model? What is an example? What are the 2
types and how do they occur? - ANSWER -states you need two
mutations for cancer
ex.) Retinoblastoma: AD with incomplete penetrance
1) Bilateral runs in family
-one copy bad already from inheritance
-second copy is sporadic mutation
2) Unilateral:
-1st copy appears sporadically via mutation
-second copy is sporadic also sporadic
What are oncogenes? Where do they come from? What genotype is
associated? - ANSWER -result from gain of function mutation of growth
promoting genes
-the normal gene is called proto-oncogene
-usually dominant mutation
, What are mutations that occur in tumor suppressor genes? What is
affected? What genotype is associated? - ANSWER -loss of function to
inhibit the growth inhibiting activates
-need to be recessive
What are the DNA repair genes? What is their function? - ANSWER def:
help maintain integrity of the genome
-BRCA1, BRCA2, Mismatch (MLH and MSH)
How does the cell cycle work? What are the factors? What are they
regulated by? What are checkpoints and which is important for cancers?
- ANSWER -use cyclins and cyclin dependent kinases
-regulation done via phosphorylation and CDK inhibitors
-checkpoints: G1/S (important for cancer), S/G2, G2/M. G0
What are the function of the following in the cell cycle:
1) Rb
2) p53
3) p16
4) p21 - ANSWER 1) Rb blocks E2F
-G1-S phase checkpoint
2) p53:
-activate p21
-halt DNA rep
3) p16:
-block Cyclin D1/CDK4/6 from phosphorylating Rb
4) p21:
-inhibit Cyclin E from binding CDK2
How do you find cancer genes? - ANSWER -lost cell markers indicated
loss of heterozygosity (LOH) near gene of interest
What is GWAS? What is it used for? What techniques are used? What
can be screened? What is used to reduce burden? - ANSWER -GWAS:
genome wide association studies
-many markers screened in one test
-used microarrays or WGS
-can screen many markers such as SNPs
