Pharmacogenomics

Question 1

Pharmacogenomics is the science of…..

Answer 1

examining inherited variations in genes that determine a patents response to a drug

called “personalized medicine”

Question 2

Bases in DNA

Answer 2

purines = Adenine and guanine
pyrimidines = thymine and cytosine

in RNA, uracil is present instead of thymine

Question 3

Four major types of CYP enzyme variations based on effect on drug metabolism

Answer 3

Ultra rapid metabolizer
extensive metabolizer
intermediate metabolizer
poor metabolizer

Question 4

Which drugs require HLA testing

Answer 4

Abacavir + drugs that contain it = HLA-B5701

Allopurinol = HLA-B5801

Carbamazepine, Oxcarbazepine, Phenytoin, Fosphenytoin = HLA-B1502

Question 5

Which polymorphism to test for in Clopidogrel pts

Answer 5

CYP2C192/3 alleles then dont use drug

Question 6

Which polymorphism to test for in Codeine patients

Answer 6

CYP2D6, dont use if ultra-rapid metabolizer or poor metabolizer

Question 7

Which polymorphism to test for in Warfarin

Answer 7

CYP2C92/3 and VKORC1

if any present, start with lower dose due to inc bleeding risk

Question 8

Before taking Trastuzumab (Herceptin), should test for….

Answer 8

HER2 gene

if tumor is negative, then drug won’t be effective

Question 9

Before taking Cetuximab (Erbitux), should test for….

Answer 9

KRAS mutation

if positive for KRAS mutation, dont use

Question 10

Before taking Azathioprine (Azasan), should test for…..

Answer 10

TPMT

if TPMT activity is low/absent, start at a very low dose or use an alternative txm

Question 11

Before taking Capecitabine (Xeloda) or Fluorouracil, test for……

Answer 11

DPD deficiency

if DPD deficient, then dont use