Ethnic variations

Essential to the definition of Pharmacogenetics is the term genetic polymorphism. It is extrapolated that there are at least three million genetic polymorphisms in the human genome. Historically, a genetic polymorphism was defined as a genetic variation with a population frequency of 1% and above, but the larger inter-ethnic variation of population frequencies makes a strict definition based on such frequencies impractical. The most common molecular type of polymorphism is the... 

This volume covers topics including cultural perspectives in psychiatric diagnosis and psychopharmacotherapy, differences in pharmacokinetics and pharmacodynamics of psychotropics, pharmacogenetics of ethnic populations, ethnic variations in psychotropic responses, complementary medicines in mental disorders, attitudes towards psychotropic medications, prescribing practices in Asia-Pacific countries, pharmaco-economic implications, integrating theory and practice, and... 

Murphy, H. B. (1969). Ethnic variations in drug response results of an international survey. Transcultural Psychiatric Res., 6, 5-23. 

As is apparent from the literature reviewed above, that culture and ethnicity are powerful determinants of an individual s response to psychopharmacotherapy. Progress in this regard will vastly improve our current practice in using medications. However, it is necessary to remember that there are often very substantial inter-individual variations within any defined cultural or ethnic group, and that ethnic variations in pharmacological responses should not be interpreted stereotypically. 

One approach to formulating potential differences in ethnic response is to examine the metabolic pathways of the common antipsychotics and determine whether the known ethnic variations in metabolizing enzymes or other effects on absorption, distribution, and excretion can be applied a priori to predict potential clinical effects. In this section we will consider some of the commonly prescribed SGAs, and only briefly touch on the FGAs. 

Patel, N. C., Crismon, M. L., Shafer, A., De Leon, A., Lopez, M. et al. (2006). Ethnic variation in symptoms and response to risperidone in youths with schizophrenia-spectrum disorders. Soc. Psychiatry. Psychiatr. Epidemiol., 41, 341-6. 

Identifying inter-ethnic variations in psychotropic response in African Americans and other ethnic minorities... 

Lithium presents yet another model of ethnic variation in side effects and response. It is well established that African Americans show a higher red blood cell (RBC) to plasma ratio of lithium concentration when compared to Asians and... 

Figure 15.1 Cross-ethnic variations in psychopharmacology influences of genetics, environment, and culture...

Nowadays most trials of psychotropic drugs are multicentric, and an increasing number of them are carried out in different regions of the world. However, ethnic variations in response to the tested drugs are rarely a focus of attention in these trials. Moreover, treatment guidelines produced in North America and Europe are often regarded as universally valid, and rarely adapted to other regional contexts. This is still partly due to some reluctance to accept the concept of ethnic variability,... 

Ethnic variation in allele frequencies can lead to important differences in disease susceptibility, outcome and drug metabolism [68, 69]. In addition to single nucleotide polymorphisms, variable number of tandem repeat (VNTR) regions have been shown to have functional significance. 

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