Genetic variation additive

Genetic variation of pathogenic agents in microorganism-caused disorders can be an additional source of individual drug sensibility. Since this article only focuses on human polymorphisms, we will illustrate this concept with one example. 

Evolution of chemical defenses according to the optimal defense theory presumes, in addition to costly defenses, that there is genetic variation for the defensive metabolites, that herbivory is the major selective agent for such metabolites, and that the chemical trait in question is efficient in reducing herbivory (Stamp 2003). Research on macroalgal chemical defenses has strongly emphasized the last precondition, which has mainly been studied by testing the deterrence effects of secondary metabolites in bioassays. The defensive role for the trait has been assumed on the basis of deterrence it provides. Veiy little research on the first two... 

The QT interval is a dynamic physiological variable depending on multiple factors such as cardiac cycle length (heart rate), autonomic nervous system activity, age, gender, plasma electrolyte concentrations, genetic variations in ion channels involved in cardiac repolarization. In addition, circadian and seasonal variations of the QT interval have been described [93]. 

Since human populations are outbred and therefore characterized by genetic variation, these differences are also observed at the protein level. In addition, factors such as the environment and lifestyle have presumably a great influence on genetic and protein backgroimds. hi summary, it is critical to filter out the disease-specific changes from changes that are the result of polymorphic differences (Anderson and Anderson 2002). 

Post-translational modifications were recognized as additional sources of the structural modification of proteins.(22) Should such a modification occur by an enzyme-mediated process, as had been established for oxidation of sulfhydryl groups or the addition of carbohydrate or phosphate groups, or by the cleavage of the polypeptide with loss of a terminal amino group, or a larger part of the chain, it too could be subject to genetic variation. 

Induction occurs predominantly at the level of transcription (Fig. 1), often being regulated by specific receptors that interact with the chemical inducer (Fig. 2 Table 1). During the last decade it has become feasible to study the impact, on DME expression, of polymorphisms in regulatory factors in addition to genetic variation in coding regions of enzymes themselves. In a few instances, elevation of enzyme level and enzyme activity is... 

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