Week 18 - Gene-environment interactions in depression

Question 1

What is the name of the type of study which is used to identify genetic factors that may be involved in a particular trait?

Answer 1

A genetic association study

Question 2

Which gene might be a good candidate to study to see if there is any genetic association with depression?

Answer 2

The BDNF gene

Question 3

What is a pre-pro-protein?

Answer 3

An inactive protein that is modified in order to produce a pro-protein, which is further modified to produce the active, mature form of the protein

Question 4

What is a pro-protein?

Answer 4

An inactive protein that is modified in order to produce the active, mature form of the protein

Question 5

What is meant by the term cohort study?

Answer 5

A type of longitudinal study that follows a particular group/groups of people over time

Question 6

A genetic variation which causes an amino acid change from a valine to a methionine has what effect on the secretion of BDNF?

Answer 6

It impairs it

Question 7

What is the BDNF Val66Met variant?

Answer 7

A genetic variant where an amino acid is changed from a valine to a methionine at the amino acid position 66 of the pro-BDNF sequence

Question 8

What conditions has the BDNF Val66Met variant been associated with?

Answer 8

• Alzheimer’s disease
• Schizophrenia
• Eating disorders
• Depression

Question 9

What is meant by the term transgenic?

Answer 9

An organism where one or more genes from a different organism or species have been transferred into their genome

Question 10

How is the term ‘gene-environment interactions’ often abbreivated?

Answer 10

GxE

Question 11

Who carried out one of the first GxE studies in depression, and when was it?

Answer 11

Caspi et al., 2003

Question 12

What did the study carried out by Caspi et al show with regards to depression?

Answer 12

That one functional variant of the serotonin transporter gene increased the risk of depressive symptoms following exposure to stressful life events

Question 13

What effect does the BDNF Val66 variant have on the depressive response to high levels of stress?

Answer 13

It increases it

Question 14

What is meant by the term forest plot?

Answer 14

It is a graphical display of the findings of meta-analysis, which summarises results from a number of studies together with the results of the meta-analysis

Question 15

What is the vertical line on a forest plot known as?

Answer 15

The line of no effect

Question 16

What does the size of each point on a forest plot indicate?

Answer 16

The size of the study

Question 17

In a forest plot, where will you see studies with the greatest difference between conditions?

Answer 17

Furthest from the line of no effect

Question 18

What is a two-tailed statistical test?

Answer 18

It is a test used to determine the difference between two data sets in either direction

Question 19

What is a one-tailed statistical test?

Answer 19

A test used to determine the difference between two data sets in one direction only

Question 20

What are the main epigenetic mechanisms?

Answer 20

DNA methylation and histone acetylation

Question 21

What is meant by the term epigenome?

Answer 21

The genome together with any epigenetic modifications that occur through out life

Question 22

Within chromosomes, what is DNA coiled around?

Answer 22

Proteins called histones

Question 23

What j