Parm Exam 1 (3-4) Flashcards
e.g. rs10516526
SNPs: Single nucleotide polymorphism
e.g. rs10516526 G
Alleles: Different DNA sequences at a locus
e.g. rs10516526 GG, GA, or AA
Genotypes: Pair of alleles at a particular locus
A set of DNA variations, or polymorphisms, that tend to be inherited together.
Haplotype:
Factors Affecting Drug Response
1 Environment:
Diet
Lifestyle
Socioeconomics
Others.
2 Biology:
Age
Sex
Others
3 Genetics*
the study of how genes affect a person’s response to drugs
Pharmacogenomics
Systemic Approach to Genetic Variations
Identify the Genetic variations and what can be affected:
Enzyme, transporter, receptor, disease.
Silent: no functional effect.
Determine who is impacted:
Individuals or population.
Identify how it is relevant to drug:
Affect drug PK or drug PD.
Resulted in drug efficacy, toxicity or drug dosing
Has no effect.
Determine how Relevant to a disease:
Increase or decrease drug susceptibility or condition.
Utility as a screening or diagnostic tool.
Phase I
mods:
Hydroxylation
Hydrolysis
Oxidation
Reduction
HHOR (whore)
ex: P450 CYPs
Phase II
mods: Conjugation
Ex:
UGT: Glucuronidation
NAT: Acetylation
GST: Glutathione conjugation
SULT: Sulphation
MT: Methylation
GAGS M(e)
Genetic variations and Enzymatic activity (Phenotypes):
Extensive metabolizers (EM or WT):
Individuals who are homozygous for the two alleles coding for “normal” enzyme function.
Poor metabolizer (PM):
Individuals who are homozygous with two variant alleles resulting in inactive or absent enzymes.
Intermediate metabolizer (IM):
Those who are heterozygous manifest phenotype with reduced function of heterozygous EM.
Ultra-rapid metabolizer (UM):
Resulted from gene duplication or multiplication.
PGx of transporter MDR1
Reduced gene Expression -> Higher drug plasma level ex: Digoxin -> C1236T, C3435T, G2677T/A
Breast Cancer Alternative treatments
Aromatase Inhibitors:
Blocks aromatase enzyme:
Convert androgen into estrogen.
Anastrazole
Letrozole
Warfarin/Coumadin GG 1/1 and 1/2 dose
5-7mg
Warfarin/Coumadin GG 2/3 dose
3-4mg
Warfarin/Coumadin GG 3/3 dose
0.5-2mg
Irinotecan
UGT1A1*28
Neutropenia
Codeine (prodrug)
CYP2D6
PM: No analgesic effect
UM: respiratory depression
Clopidogrel (prodrug)
CYP2C19
PM: No drug activity