Sorted By Test Name - Mayo Medical Laboratories

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