Ch. 11 Pharmacogenomics

Question 1

Purines

Answer 1

Adenine

Guanine

Question 2

Pyrimidines

Answer 2

Thymine

Cytosine

Question 3

Haplotype

Answer 3

A group of genes or DNA variations inherited from a single parent that exist on the sam chromosome and are likely to be inherited together

Question 4

Single nucleotide polymorphism (SNP)

Answer 4

A change in a single nucleotide in a genetic sequence. Most common genetic polymorphism in DNA. Responsible for the majority of individual variability in response to a drug

Question 5

Mutation associated with Abacavir

Answer 5

HLA-B*5707 (if positive DO NOT USE)

Question 6

Type of reaction associated with HLA-B*5707

Answer 6

Fatal hypersensitivity

Question 7

Drugs that contain abacavir

Answer 7

Epzicom
Triumeq
Trizivir

Question 8

Mutation associated with Allopurinol

Answer 8

HLAB*5801 (if positive DO NOT USE)

Question 9

Type of reaction associated with HLA-B*5708

Answer 9

Increased risk of SJS

Question 10

Population to test prior to use of allopurinol

Answer 10

Patients with significant renal impairment or those with Han Chinese or Thai ancestry

Question 11

Mutation associated with Carbamazepine and phenytoin/fosphenytoin

Answer 11

HLA-B*1502 (if positive DO NOT USE)

Question 12

Type of reaction associated with HLA-B*1502

Answer 12

SJS, TEN

Question 13

Population to test prior to starting carbamzepine

Answer 13

All Asian patients

Question 14

Mutation associated with Clopidogrel

Answer 14

2C192/3 (if pt has the allele, consider alternatives)

Question 15

Effect of therapy in patients with 2C19 mutation in clopidogrel use

Answer 15

Poor metabolism of clopidogrel (as it is a prodrug) and increased cardiovascular events

Question 16

CYP450 enzyme associated with Codeine metabolism

Answer 16

2D6

Question 17

Codeine use in 2D6 ultra-rapid metabolizers

Answer 17

Increase in production of morphine, resulting in toxicity

Question 18

Codeine use in 2D6 poor metabolizers

Answer 18

Lack of efficacy

Question 19

CYP450 enzyme associated with use of Warfarin

Answer 19

2C92/3 and VKORC1

Question 20

Effect of warfarin in patients expressing 2C92/3 and/or VKORC1

Answer 20

Increased bleeding risk, lower dose if variations of alleles are present

Question 21

Gene expression needed in those to start Trastuzumab therapy

Answer 21

HER2 overexpression

If tumor is HER2 negative, do not use

Question 22

Cetuxumab and panitumumab gene mutation

Answer 22

KRAS

Question 23

If a patient is KRAS positive, they cannot use

Answer 23

Cetuximab and panitumumab

Question 24

Gene associated with AZA use

Answer 24

TPMT

Question 25

Low/absent TMPT activity in AZA use can cause

Answer 25

Myelosuppression

Question 26

Enzyme associated with Capecitabine and Fluorouracil use

Answer 26

Dihydropyrimidine dehydrogenase (DPD)

Question 27

Deficiency in DPD and use of Capecitabine and Fluorouracil can cause

Answer 27

Increased toxicity (diarrhea, neutropenia, neurotoxity)
Do not use in patients with DPD deficiency

Question 28

If a patient produces less VKORC1, they require

Answer 28

A lower dose of warfarin

Question 29

Which isomer type of warfarin is better metabolized by 2C9?

Answer 29

S-isomer is more potent than the R isomer