L2 ( CYP 2D6 ) Flashcards
True or false?
CYP 2D6 enzyme responsible for metabolism of the following drugs :
1️⃣Analgesics (codeine, tramadol).
2️⃣Antiarrhythmics (propafenone, flecainide).
3️⃣β-blockers (metoprolol, propranolol, bupranolol, and carvedilol).
4️⃣Antipsychotics (haloperidol, clozapine, and risperidone).
5️⃣Tricyclic antidepressants (desipramine, amitriptyline, imipramine).
6️⃣Selective serotonin reuptake inhibitors (fluoxetine, paroxetine, sertraline).
7️⃣Estrogen receptor antagonist (tamoxifen).
8️⃣opioids (codeine and tramadol)
True ✅
True or false?
Polymorphisms in the CYP2D6 gene are the best characterized among all
of the CYP variants.
True ✅
True or false?
Over the years, at least 100 gene variants and 120 alleles have been
identified in the CYP2D6 gene. Despite the extensive number of alleles, genotyping 12 SNPs could
provide 90% to 95% accuracy in predicting the real phenotype.
True ✅
True or false?
CYP2D6*2, gene duplication or amplification, with resultant higher enzyme activity in the ultra rapid metabolizer (UM) phenotype (carriers of multiple
copies of functional alleles).
True ✅
True or false?
The two null variants, CYP2D64 (c.1846G>A, defective splicing) and
CYP2D65 (gene deletion), are found in poor metabolizer (PMs) and result in an inactive enzyme and absence of enzyme, respectively.
True ✅
Complete the sentence:
Other than CYP2D62 which10 and *17, *9, *29, *36, and *41 variants are also associated with
lower enzyme activity in the intermediate metabolizers (IMs) phenotype (carriers of one nonfunctional allele and one allele with diminished activity).
True or false?
In pharmacogenomics of CYP 2D6 :
The therapeutic implication of CYP2D6 polymorphism is different if the
substrate in question is a prodrug.
True ✅
True or false?
In pharmacogenomics of CYP 2D6 :
Poor metabolizer (PMs) would not be able to convert the drug into the
therapeutically active metabolite.
True ✅
True or false?
In pharmacogenomics of CYP 2D6 :
Patients who are extensive metabolizer (EM) have a wide range of
CYP2D6 activity, with ultra rapid metabolizer (UM) possessing very high
enzyme activity on one end of the spectrum and IMs possessing
diminished activity on the other end.
True ✅
True or false?
CYP2D6 PMs ( poor metabolizer) exhibit a higher incidence of undesirable side effects when taking CYP2D6-dependent antidepressants, antipsychotic drugs and selective serotonin reuptake inhibitors (SSRIs).
True ✅
True or false?
CYP2D6 UMs ( ultra rapid metabolizer) experience diminished response to these drugs.
True ✅
Complete the sentence:
Two examples of prodrugs dependent on CYP2D6 are …..
Analgesics (codeine, tramadol).
True or false?
Codeine and tramadol are converted by CYP2D6 to morphine and O-desmethyltramadol, respectively.
True ✅
True or false?
CYP2D6 UM ( ultra rapid metabolizer) genotype exhibited about a 50% higher concentration of morphine compared with the EM ( Extensive metabolizer)genotype. However, individuals having defective alleles of CYP2D6
exhibited very low or undetectable morphine concentrations with a lack of analgesia.
True ✅
True or false?
CYP2D6-catalyzed conversion of tamoxifen ( Estrogen receptor antagonist ) to the more potent anti-estrogen metabolite, endoxifen.
True ✅
