Genotypic subgroups

PMs in such groups by phenotyping is not as clear-cut as in European- and Southeast Asian-derived populations this problem is compounded by the low prevalence of this subgroup in these populations. This would appear to be one situation in which putative classification as a PM requires confirmation by genotyping. 

There are few pharmacogenetic data for Hispanics. As previously stated, not every Hispanic subgroup has been phenotyped. To the best of our knowledge, our research unit is the only one that has reported on the results of CYP2D6 genotyping in Mexican Americans (Mendoza 1996). There are, however, data regarding isozymes that are thought to be fairly specific to Asians, Africans, and Spaniards. 

Fig. 1. Principle of calculation of genotype-based dose adjustments based on differences in pharmacokinetic parameters, such as clearance and area under the curve. The theoretic dosages for genetic subgroups of poor (PMs), intermediate (IMs), extensive (RMs), and ultrarapid metabolizers (UMs) are depicted as schematic genotype-specific dosages to obtain equal plasma concentration time courses. C, concentration T, time. (From Kirchheiner J, Nickchcn K, Bauer M, et al. Pharmacogenetics of antidepressants and antipsychotics the contribution of allelic variations to the phenotype of drug response. Mol Psychiatry 2004 9(5) 442-73 with permission.)...

MILMAN, U., BLUM, S., SHAPIRA, C., ARONSON, D., MILLER-LOTAN, R., ANBINDER, Y., ALSHIEK, J., BENNETT, L., KOSTENKO, M., LANDAU, M., KEIDAR, S., LEVY, Y, KHEMLIN, A., RADAN, A. LEVY, A. P. 2008. Vitamin E supplementation reduces cardiovascular events in a subgroup of middle-aged individuals with both type 2 diabetes mellitus and the haptoglobin 2-2 genotype A prospective double-blinded clinical trial. Arterioscler Thromb Vase Biol, 28, 341-7. 

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