Prevalence of CYP2D6 gene duplication in Egyptian patients with neuropathic pain

الملخص EN

The polymorphic cytochrome 2D6 (CYP2D6) causing ultra-rapid metabolism due to presence of multiple copies of active CYP2D6 genes is common in Middle East population.

The CYP2D6 genotype of Egyptian population was examined using allele- specific polymerase chain reaction (PCR) amplification.

Among thirty neuropathic pain patients studied, twenty patients (66.6 %) were positive in the duplication assay.

Alleles that cause diminished enzyme activity were frequently found, like CYP2D6*17 (African gene) (23.3 %) and allele CYP2D6*4 (European gene) which showed a frequency of (16.6 %).

None of the patients was homozygous for CYP2D6 *4; strongly suggesting that no poor metabolizer (PM) individuals in the studied population.

This is in agreement with earlier phenotyping study among Egyptians.

The patients studied showed a rapid and obvious response to oral tramadol (50 mg, tads) .Results imply that gene deletion may not be the only modulatory factor responsible for the clinical outcome following tramadol therapy.