Cytochrome p450 enzyme polymorphism frequency in indigenous and native american populations: a systematic review.

Objective: The purpose of our study was to evaluate the evidence on the prevalence of cytochrome P450 enzyme polymorphisms as potential genetic factors influencing drug efficacy and safety in the indigenous populations of the American hemispheres.

Methods: We conducted a systematic review of studies published between 1985 and 2006 using the Pubmed database.

Results: We identified only 10 original research studies on CYP2A6, CYP2D6, CYP2C9, CYP2C19 and CYP2E1 in 13 indigenous American populations. Interethnic differences in the frequency of CYP450 genetic variants existed both among the examined indigenous populations and in comparison with African, Asian and European populations.

Conclusions: There are surprisingly few data on CYP450 enzyme polymorphisms in indigenous American populations, and it is difficult to draw any clear inferences about how these populations might be expected to respond to drugs in relation to other racial or ethnic groups. This lack of information could create a barrier to the use of pharmacogenetic testing in these populations. Collaborative partnerships between indigenous communities and researchers are needed to avail the clinical benefits of CYP450 enzyme polymorphism testing to indigenous populations.