Lecture 25 - Pharmacogenetics Flashcards
When examining inherited differences in drug responses, what two factors should be considered?
- drug efficacy
2. adverse drug reactions
Which of the following is not listed as important in recommended dosing?
A. Age B. Sex C. Body weight D. Presence of organ failure E. Trial and error F. Other Drugs
B. This is not a typical factor in dosing recommendations.
What is the drug mechanism of trastuzumab?
Targets the Her2 protein to treat metastatic breast cancer
What is the approved companion diagnostic test for Gleevac, which targets cell surface RTK c-kit?
c-kit immunohistochemical tests
Why are companion diagnostic tests important?
They help to determine a patient’s potential response to a particular drug.
Why is “reverse” genetic genotype-to-phenotype analysis performed?
To reveal how genomic variability translates to phenotypic variability (i.e. drug responses)
How many SNPs are present in humans (i.e. >1% of the population)?
10,000,000 SNPs
SNPs act by 3 general mechanisms - what are they?
- Coding non-synonymous (change coding sequence)
- Coding synonymous (no change in coding sequence; could change translational efficiency)
- Noncoding (promoter, intron, regulatory region)
Which of the 3 SNP mechanisms is responsible for altering the translational efficiency because the SNP generates a non-preferred codon?
Coding synonymous SNPs
If insertions/deletions are large enough, they can be considered:
CNVs (copy number variants)
Which of the 3 SNP mechanisms is responsible for a change in the coding sequence?
Coding non-synonymous SNPs
A ___________ is a variation in a number of a specific segment of DNA found in one or more populations.
CNV (copy number variant)
A duplication in the specific segment of the CYP2D6 gene is 10000 bp and associated with the “ultra-rapid metabolizer phenotype”. What genetic polymorphism is responsible?
CNV (copy number variant)
A given genetic polymorphism may affect drug action if it alters ___(list 4 targets)____ of a relevant gene target.
- expression level,
- subcellular localization,
- stability, or
- activity
Genome Wide Association Studies (GWAS) have shown that _______ account for the most genetic variation associated with complex human traits.
non-coding SNPs
Most genetic variants (including SNPs) that are likely to alter drug response are NOT contained where?
WithIN gene coding regions