Behav. Sci. Genetics. Flashcards
what do mutated genes give you?
an increased RISK for disease - not the actual disease
what are the highly implicated genes in schizophrenia?
COMT, NRG1, ErbB4, MTHFR-T, AKT
what are the dopamine genes?
tyrosine hydroxylase, dopamine D2 receptor, dopamine D3 receptor
the more genes mutated….
the higher the risk for disease
what causes hypofrontality?
COMT and DAR abnormalities
n-back test in schizophrenia
due to hypofrontality, unable to do n-back test (3-4-1, what is the number before 1?)
what are likely causes of limbic hyperactivity?
hypofrontality (losing glutamate excitability from frontal cortex) or maybe hypersensitive dopamine receptors
genes that become mutated in ADHD
dopamine is bad in ADHD: DISC1 (neuromigration gene), DRD1, DRD2, DRD4, DAT1 (dopamine transporter gene)
what are the causes of ADHD?
gene mutations (esp DRD4 and DRD5) with environmental factors (low birth weight, fetal stress, prematurity)
which part of the brain is hyper activated in ADHD?
reward center
genes implicated in major depressive disorder
DAT, DRD4, COMT (if enough of these mutations occur, schizophrenia symptoms may develop
areas of the brain hyper activated and hypo activated in depression
hyperactivated: VMPFC/amygdala (ventro medial pre frontal cortex). hypoactivated: frontal cortex
how is serotonin made? packaged?
from tryptophan. packaged by VMAT2
how is serotonin terminated?
SERT serotonin transporter, MAO-B destroys inside cell, MAO-A or B outside
hyperfunctioning of limbic pathway causes….due to…..
panic, worry, obsession, depression…… due to LOW serotonin (circuit is hot because serotonin is not) or HIGH NE
genes implicated in MDD, anxiety, eating, personality disorder
5-HT2A 102 T/C (reuptake of serotonin), 5-HTTLPR promoter, TPH (tryptophan hydroxylase (make serotonin)
NE is made from what? packaged?
tyrosine -> dopa -> dopamine -> NE. packaged by VMAT2 also
hypofunctioning of limbic pathway causes…..
ADHD, depression
NE dysfunction can cause….
both reduced positive affect or increased negative affect
increased negative affect causes what?
depressed mood, guilt/disgust, fear/anxiety, hostility, irritability, loneliness
reduced positive affect causes what?
depressed mood, loss of happiness, loss of interest/pleasure, loss of energy/enthusiasm, decreased alertness, decreased self-confidence (robotic like)
what drug is used in reduced positive affect?
bupropion (DA dysfunction)
what drug is used in increased negative affect?
SSRI’s (low serotonin)
anterior cingulate is low in…… and hot in…….
low in ADHD (SQUIRREL); hot in PTSD
COMT met alleles = ?
low degradation, increased NE and anxiety in limbic areas
COMT val alleles = ?. common in what disorder?
high degradation, low NE in cortex. common in ADHD because frontal cortex has less NE activity so less attention
COMT
destroys DA extracellulary (also NE)
women and MOA-A genes
found on X chromosome. no X-inactivation could lead to double the MOA activity, causing low NE and DA availability in cortex allowing for depression to occur
memorizing causes what?
disruption in empathic response
