Genetic and epigenetic medicine

Question 1

what does genomic medicine discovery reseach assess?

Answer 1

genotype phenotype association

Question 2

human genome has how many bases?

Answer 2

3 million

Question 3

___% of the human genome is the same in all people

Answer 3

99.9

Question 4

what are the differences in DNA called between different people (the 0.1%)

Answer 4

polymorphisms

Question 5

what is the most common polymorphism?

Answer 5

single nucleotide polymorphism- involves only one base

Question 6

TF: single nucleotide polymorphisms have no effect on health

Answer 6

false
sometimes they have no effect but others they can lead to a change in function which increases your predisposition to a disease

Question 7

how can we assess which nucleotide polymorphisms cause disease?

Answer 7

by comparing the single nucleotide polymorphisms in health people with patients diagnosed with certain diseases

Question 8

what are the studies investigating the associations between disease and healthy polymorphisms?

Answer 8

genome wide association studies

Question 9

what happens in genome wide association studies?

Answer 9

compare DNA of 2 groups of similar people with and without the disease
single nucleoptide polymorphism arrays read their DNA, if one variant is more frequent in people with the disease that polymorphism is said to be associated with the disease

Question 10

what is functional genomics

Answer 10

investigation of large datasets produced by the genome aiming to determine the function of genes, RNA and proteins

tries to make sense iof the results of genomic association studies

want to find out the FUNCTIONS of the genes

Question 11

how does genomics differ from functional genomics?

Answer 11

functional genomics focuses on the dynamic aspects such as:
gene transcription
translation
protein protein interactions

as oppose to just genomic information such as sequence and structure

Question 12

what is comparative genomics?

what can this help us understand

Answer 12

aims to compare the genome sequence of different species

how genes are conserved through evolution and how they function

Question 13

what is the biobank

Answer 13

a collection of biological samples for referencing purposes

Question 14

BRCA1 and BRCA2 are what?

Answer 14

tumour suppressor genes which if mutated can lead to cancer

Question 15

what is pharmacogenomics?

Answer 15

how the cell responds to drug treatment

Question 16

what is pharmacogenetics

Answer 16

how variations in one gene can effect drug responsiveness

Question 17

effect of CYP2D6 mutation on tamoxifen therapy?

Answer 17

mutates can either be: ultra rapid or poor metabolizers.
CYP2D6 metabolises tamoxifen
can lead to sub therapeutic levels or overdose.

Question 18

what do histones organise?

Answer 18

genetic material

Question 19

what are histones made of

Answer 19

protein

Question 20

charge of histones?

Answer 20

positive as they have a high percentage of basic amino acids

Question 21

why do these histones associate with DNA

Answer 21

as the positive amino acids interact with the negatively charged DNA

Question 22

How can histones influence gene expression

Answer 22

the tighter the association, the more wound it is and therefore less transcription

Question 23

what is the most compact shape called of dna and hhistone association. the dna here is ______

Answer 23

heterochromatin

inactive

Question 24

what is euchromatin

Answer 24

nucleosome structure made of four histones ‘core histones’

contains a single copy of genetically active DNA

Question 25

what does the epigenome influence?

Answer 25

which genes are active and which are turned off

Question 26

TF the epigenome cannot change in your life

Answer 26

false

Question 27

TF lifestyle and environment can change the epigenome

Answer 27

yes

Question 28

where do epigenetic changes mostly occur?

Answer 28

on histone proteins

Question 29

epigenetic changes on histone proteins include?

Answer 29

methylation, acetylation, phosphorylation, ubiquitination

Question 30

_____ and ______ resides can be methylated

Answer 30

lysine

arginine

Question 31

what is acetylation?

Answer 31

addition of acetyl groups on lysine resides

Question 32

what is acetylation of lysine resides on histones catalysed by?

Answer 32

histone acetyltransferase enzymes

Question 33

what catalyses deacetylation?

Answer 33

histone deacetylases

Question 34

acetylation is associated with _______ of transcrption

deacetylation is associated with _______ of transcription

Answer 34

induction

repression

Question 35

TF

cancers are caused only by changes to the genome not the epigenome

Answer 35

false

a combination

Question 36

what were histone deacetylase 1 and 2 both correlated with?

Answer 36

increased proliferating capacity

Question 37

what can DNA hypermethylation cause? where is this often seen?

Answer 37

transcriptional inactivation of genes

observed in tumours

Question 38

a decrease in DNA methylation ______ genes

Answer 38

activates

Question 39

how can we use a therapy to result in the re-expression of transcriptional incompeted chromatin

Answer 39

inhibit certain active histone methyltransferases

can lead to repression of genes

Question 40

decitabine and azacitidine mechanisms of action?

Answer 40

blocks DNA methyltransferase causing hypomethylation of DNA

may reverse inactivation of suppressor genes

Question 41

decitabine and azacitidine side effects

Answer 41

bone marrow suppression

cytotoxicity

Question 42

in carcinogenesis how can TSGs be silenced. how can we target this

Answer 42

by DNA methylation

so can use a drug to inhibit DNA methyltransferases to re express the TSGs

Question 43

MOA of temozolomide

Answer 43

kills cancer cells by adding methyl groups to DNA

Question 44

decitabine is a _______ ______. what does it inhibit

Answer 44

nucleoside analoge

inhibits DNA methyltransferases by trapping them in a covalent complex on DNA thus resulting in enzyme degradatoin