Mayo Test Catalog, (Sorted By Test Name) - Mayo Medical ...

elationship between the polymorphisms detected in this assay and the effect on the activity of the
enzyme produced by that allele: CYP2D6 Allele Nucleotide Change Effect on Enzyme Metabolism *1
None (wild type) Extensive metabolism (normal) *2 2850C->T Decreased activity *2A 2850C->T and
-1584C->G Increased activity *3 2549delA No activity *4 1846G->A No activity *5 Gene deletion No
activity *6 1707delT No activity *7 2935A->C No activity *8 1758G->T No activity *9 2613delAGA
Decreased activity *10 100C->T Decreased activity *11 883G->C No activity *12 124G->A No activity
*14A 100C->T and 1758G->A No activity *14B 1758G->A Decreased activity *15 138insT No activity
*17 1023C->T Decreased activity *41 2988G->A Decreased activity Gene duplication Depends on the
allele duplicated (increased/no effect) A complicating factor in correlating CYP2D6 genotype with
phenotype is that many drugs or their metabolites are inhibitors of CYP2D6 catalytic activity. SSRIs, as
well as some TCAs and other xenobiotics, may reduce or increase CYP2D6 catalytic activity.
Consequently, an individual may require a dosing decrease greater than predicted based upon genotype
alone. It is important to interpret the results of testing in the context of other coadministered drugs.
Useful For: Identifying patients who are poor or extensive metabolizers of antidepressant drugs
metabolized by CYP2D6 Adjusting dosages for antidepressant drugs that are metabolized by CYP2D6
Interpretation: An interpretive report will be provided. Based on the test sensitivity and currently
available CYP2D6 polymorphism carrier frequencies, persons of Caucasian descent who tested negative
for the above polymorphisms would be estimated to have a