Animal Models (29,30)

Question 1

What is true about mice and human genomes?

a. Amino acid homology between mice and humans is lower than sequence homology
b. Mice were the first mammal to have its genome sequenced
c. Humans and mice share 50% of their genes
d. Genes that are similar between mice and humans have 85% sequence homology

Answer 1

d. Genes that are similar between mice and humans have 85% sequence homology

Question 2

The ob gene:

a. Results in undernourished mice when it is knocked out
b. Encodes a leptin that signals satiety
c. Has been studied using gene knock-in technology
d. Was mutated on purpose in Jackson laboratories

Answer 2

b. Encodes a leptin that signals satiety

Question 3

How can knock out mice be generated?

a. Non-homologous recombination and end joining using a null gene insert
b. Mutating white mouse ESC and injecting into black mouse blastocysts to form chimera
c. Breeding agouti mice that are homozygous for the mutation due to recombination
d. Tetraploid complementation to ensure that mutant white mice give rise to mutant chimera

Answer 3

b. Mutating white mouse ESC and injecting into black mouse blastocysts to form chimera

Question 4

To compare WT and KO mice that are siblings and avoid genotype differneces, what would be the genotype of the parents?

a. WT/WT X KO/KO
b. WT/KO X KO/KO
c. KO/KO X KO/KO
d. KO/WT X KO/WT

Answer 4

d. KO/WT X KO/WT

Question 5

How can mice offspring be genotyped as WT or KO?

a. PCR
b. Southern Blotting
c. Microarray
d. Cre-Lox analysis

Answer 5

a. PCR

Question 6

What is developmental compensation?

a. An induce KO mutation reverts to WT spontaneously
b. The Consequence of a deletion are masked due to up-regulation of genes/systems that compensate for loss
c. KO mice can only be generated conditionally and during adulthood
d. The likelihood of a KO mutation being embryonic lethal

Answer 6

b. The Consequence of a deletion are masked due to up-regulation of genes/systems that compensate for loss

Question 7

What is a feature of the Cre-Lox system?

a. It is used to conditionally generate gene knock-in mice
b. It can only provide temporal control
c. Once cre is introduced to a mouse, it will be active in every cell
d. Cre excises floxed DNA to produce KO mutations

Answer 7

d. Cre excises floxed DNA to produce KO mutations

Question 8

What element would NOT be a targeted knock in?

a. Floxed version of an endogenous gene
b. A mutation relating to human disease
c. A null gene
d. A marker gene, such as florescence or an enzyme

Answer 8

c. A null gene (used to KO)

Question 9

Which human disease has been modelled in mice using targeted knock in technology?

a. Parkinson’s disease
b. Type 1 diabetes
c. Huntington’s disease
d. Breast Cancer

Answer 9

c. Huntington’s disease

Question 10

A feature of using bacterial artificial chromosomes (BACs) in manipulating the mouse genome is:

a. They contain the gene of interest and a large amount of its regulatory sequence
b. They integrate specifically into the genome
c. The size limit means that flurophores cannot be used in BAC vectors
d. BACs are used to speciafically KO genes, such as the mouse homolog that causes Huntington’s in humans

Answer 10

a. They contain the gene of interest and a large amount of its regulatory sequence

Question 11

• Mice are useful models for human disease as they are mammals with similar genomes, physiology and behaviours to humans.

Answer 11

T

Question 12

• The differences in mice and human physiology are a major setback in using mouse models for human disease.

Answer 12

F

Question 13

What is false about studying anxiety in mice?

a. It is based on the conflict between the desire to stay safe and the desire to explore
b. More anxious mice will stay within the walled arms of elevated plus mazes
c. Less anxious mice often stay confined in the dark area of a light/dark box
d. Large open field tests cause the feeling of aversion of mice through bright light

Answer 13

c. Less anxious mice often stay confined in the dark area of a light/dark box

Question 14

What is FALSE about studying fear conditioning behaviour in mice?

a. Mice are classically conditioned to display fear freezing
b. It can model fear memory in humans
c. Wild type mice can demonstrate extinction, but PLCB4 Knock outs can’t
d. It is not reflective of post traumatic stress disorder in humans

Answer 14

d. It is not reflective of post traumatic stress disorder in humans

Question 15

What is correct about using circadian rhythm and sleep to study the behaviour of GM mice?

a. Running wheels provide little information in studying circadian rhythm
b. Mice with limited food access adjust their rhythm to fit feeding patterns
c. Sleep architecture can be studied using an ECG
d. Mice with free access to food exhibit random and unpredictable sleep patterns

Answer 15

b. Mice with limited food access adjust their rhythm to fit feeding patterns

Question 16

Why is circadian rhythm and sleep measured using both an EEG and EMG?

a. EEG patterns can look similar between states of REM and wakefulness
b. High activity indicated by an EMG can indicate REM sleep straight away
c. EEG patterns are usually very distinct between Wakefulness and REM sleep
d. The research is more valid if brainwaves during sleep are measured from all parameters

Answer 16

a. EEG patterns can look similar between states of REM and wakefulness

Question 17

What can pre-pulse inhibition show?

a. The stimulus filter is intact in wild type mice and those that model schizophrenia
b. A pre-pulse warning will not lessen the startle response in mice that model schizophrenia
c. Stimulus filters can be directed to specific cues using carefully timed pre-pulse stimuli
d. A pre-pulse stimulus increases the intensity of the startle response in mice that model schizophrenia

Answer 17

b. A pre-pulse warning will not lessen the startle response in mice that model schizophrenia

Question 18

Which statement about optogenetics is FALSE?

a. Channelrhrodopsins are ion channels from algae that are activated by light
b. Neurons that express ChR2 as a result of viral vector transfection can be stimulated by light
c. It has been used in experiments that demonstrate different neuronal populations in the ventromedial hypothalamus
d. Channelrhrodopsins occur naturally in mouse neurons can allow neuronal circuits to be selectively inhibited using light

Answer 18

d. Channelrhrodopsins occur naturally in mouse neurons can allow neuronal circuits to be selectively inhibited using light

Question 19

How were optogenetics used to demonstrate that different neuronal populations exist in the ventromedial hypothalamus?

a. Transgenic mice were created that failed to produce ESR1 in the presence of Cre
b. Transgenic mice only expressed Cre and Chr1 in cells which expressed ESR1
c. Chr2 expression was induced in mouse neurons and this was achieved without using the Cre-Lox system
d. When the mice were exposed to light, ESR1, Cre and Chr1 were turned off and the mice showed docile behaviour

Answer 19

b. Transgenic mice only expressed Cre and Chr1 in cells which expressed ESR1

Question 20

• Schizophrenia suffers have dysfunctional stimulus filters and this can be seen by studying sensorimotor gating in GM mice.

Answer 20

T

Question 21

• Adeno-associated viral vectors contain a lipid membrane and RNA whilst Lentiviral vectors contain a protein capsid and DNA.

Answer 21

F