Factors affecting disposition genetic

Genetic factors are particularly important in humans and can influence the response to the compound or the disposition of the compound and hence its toxicity. Several genetic factors affecting metabolism are known in which a nonfunctional, less functional, or unstable form of the enzyme is produced in a particular phenotype, for example, acetylator phenotype... 

There are many factors, both chemical and biological, which affect the disposition of xenobiotics. Chemical factors include size and structure, pKa, chirality, and lipophilicity. Biological factors include species, sex and strain, genetic factors, hormonal influences, disease and pathological conditions, age, stress, diet, dose, enzyme induction and inhibition, and tissue and organ specificity. All of these factors can affect the toxicity of a chemical by changing its disposition, especially its metabolism. 

Within human beings many factors can affect the processes of absorption of chemicals, their distribution throughout the body, metabolism, and excretion. Factors such as the age of the person, their state of health, their genetic make-up, their diet, and what drugs they are taking can all influence the disposition of a drug. 

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