Behavioral Science: Genetics in Psychiatry

Question 1

Important genes in schiz

Answer 1

COMT
Tyrosine hydroxylase
Dopamine D2 receptor
Dopamine D3 receptor

Question 2

What do abnormalities in COMT and DAR cause?

Answer 2

Hypofrontality (as seen in schizophrenia)

- we don’t know what causes the limbic hyperactivity

Question 3

Important genes in ADHD

Answer 3

DRD4

DRD5

Question 4

Important genes in MDD

Answer 4

DAT
DRD4
COMT

Question 5

What parts of the brain have high/low activity in MDD?

Answer 5

High activity: VMPFC, amygdala

Low activity: DLPFC

Question 6

What does hyperfunctioning in limbic pathways cause?

Answer 6

Panic, worry, obsession, depression

Question 7

Important genes in MDD/Anxiety/ED/Bipolar

Answer 7

5HT-2A 102 T/C
5HTTLPR promoter
TPH

Question 8

What does hypofunctioning in the frontocortical pathways cause?

Answer 8

ADHD

Depression

Question 9

DA and NE dysfunction lead to…

Answer 9

Reduced positive affect: depressed mood, loss of happiness, loss of interest/pleasure, loss of energy/enthusiasm, decreased alertness, decreased self confidence

Question 10

5HT and NE dysfunction lead to…

Answer 10

Increased negative affect: depressed mood, guilt/disgust, hostility, irritability, loneliness

Question 11

COMT Met alleles –>

Answer 11

low degradation –> increased NE and anxiety in limbic areas

Question 12

COMT Val alleles –>

Answer 12

high degradation –> low NE in cortex, less attention

Question 13

What does memorizing do to the empathic response?

Answer 13

Decreases it

Question 14

What might the brain of a low-empathy person look like?

Answer 14

Overactive cingulates, hypoactive MPFC