Personalized Medicine

Question 1

What are 3 benefits of personalized medicine?

Answer 1

• Safer drugs (reduction of side effects)
• Increased drug effectiveness (side benefit is reduced cost as well as dosages tuned to an individuals ability to metabolize)
• Alternative drugs for standard treatments

Question 2

Which alleles should be examined prior to prescription of warfarin?

Answer 2

• VKORC1 (vitamin K epoxide reductase)

- CYP2C9

Question 3

What does SNP stand for and what is it’s relevance?

Answer 3

Single nucleotide polymorphism. We all have different polymorphisms and we need to get away from one size fits all drugs.

Question 4

How can we detect a SNP?

Answer 4

• Deep sequencing (reading the genome many times to eliminate errors, generates lot of data)
• Exon trapping
• Direct sequencing (most common)

Question 5

What is the importance of cytochrome p-450 enzymes?

Answer 5

They contribute to metabolism of about half of all medications.

Question 6

An example of cytochrome p-450 enzymes is CYP3A4, which codes for the essential enzyme 3A4. 2D6 is one enzyme that is required for the metabolism of codeine to morphine. What is the balance req. of 3A4 and 2D6 to convert codein to morphine?

Answer 6

You need more 2D6 relative to 3A4.
If too much 3A4, codeine does not metabolize to morphine .
3A4 converts “codeine” to “norcodeine” which cannot be used by the body.

Question 7

Describe the 3 types of metabolizers and the significance for pain management.

Answer 7

A “poor metabolizer” (PM) cannot metabolize codeine (too little 2D6 or poor functioning 2D6 allele)

“Extensive Metabolizers” (EM) metabolize codeine

“Ultrarapid Metabolizer” metabolizes too quickly to be able to effectively benefit from the codeine (too much 2D6 or super able allele)