Variability Due to Genetic Differences Flashcards Preview

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Flashcards in Variability Due to Genetic Differences Deck (13):

What is one of the main ways people vary in how they respond to drugs?

Genetic variations in pharmacokinetics


What are inherited variations to drug response?

Inherited differences can occur in any of the proteins involved in ADME, drug receptors and targets


What is the focus of this lecture?

Inherited variation in drug metabolism (phase one) particularly CYP 450


what is CYP450?

A family of proteins with many subgroups, isoforms etc that metabolize many endo and exogenous compounds.


What is phenotypic expression

Expression of genes, also influenced by environment

Though we just focus on variation in inherited genes for this lecture.


What is polymorhpism?

When two or more phenotype exist for that gene in a population


What is the poor metaboliser trait?

Inherited loss of function in a drug metabolizing enzyme

thus increased prolonged drug in system and risks...


What is extensive metabolizers?

Normal enzyme activity


How is the poor metabolizer (PM) inherited?

Autosomal recessive mendalian manner


What may PM lead to?

Elevated drug levels in blood, thus increased risk of toxicity especially for those with a small therapautic window


What are the genetic polymorphisms phenotype for enzyme function?

PM = null action, homozygous for deleterious allele
IM = intermediate metabloizer, heterozygote carrier of a deleterious allele
EM = extensive metabolizer, normal function (homozygous wild type allele)


What is omeprazol?

a proton pump inhibitor, (H/K ATPase), prevents stomach acid secretion (parietal cells). treats peptic ulcers.


What is metabolic ratio?

Drug / metabolite

High = poor metabolizer
low = extensive