Genetics in Psychiatry Flashcards
(19 cards)
schizophrenia genes that involve DA
COMT, tyrosine hydroxylase, Dopamine D2 receptor, dopamine D3 receptor
what happens when you have more mutated risk genes?
more risk genes = greater risk for developing the neurological condition
what do COMT and DAR abnormalities cause?
hypofrontality.
mutations in COMT and DRD3 cause:
low dopamine
mutations in DRD2, Tyr-OH, and MAO cause:
high DA in the mesolimbic system
main genes involved in ADHD
DRD4 and DRD5!
what is the math formula for ADHD development?
genetic issues + environmental stress = ADHD
main genes involved in Major Depressive Disorder
DAT, DRD4, COMT. Dopamine problems -> SIGECAP symptoms
what is precursor to serotonin?
tryptophan
what does hyperfunctioning serotonin in limbic pathways cause?
panic, worry, obsession, depression. remember, a hyperfunctioning pathway may have poor serotonin activity!
serotonin genetics of Major Depressive Disorder
5-HT2A 102 T/C, 5-HTTLPR promoter, TPH. bad reuptake, bad receptors, bad synthesis -> bad serotonin.
what is precursor to norepinephrine?
tyrosine!
hyperfunctioning NE in the limbic pathways cause:
panic, worry, hyperarousal. fight or flight
hypofunctioning NE in frontocortico pathways cause
ADHD, depression
what do increased Ne and serotonin dysfunction lead to?
increased negative affect. depressed mood, guilt/disgust, fear/anxiety, hostility, irritability, loneliness
what do decreased NE and DA dysfunction lead to?
reduced positive affect. depressed mood, loss of happiness, loss of interest/pleasure, loss of energy/enthusiasm, decreased alertness, decreased self-confidence
COMT Met alleles
low degradation -> increased NE and anxiety in limbic areas
COMT Val alleles
high degradation -> low NE in cortex
what is interesting about women and MAO genes
some women have X inactivation and two copies of the MAO-A gene and double the MAO activity, leading to low NE and DA availability in the cortex, allowing for depression to occur.
