Estimation of polymorphisms in the drug-metabolizing enzyme, cytochrome gene in six major ethnicities of Pakistan.

Interindividual differences in cytochrome P450 ( 2C19 activity may result in variations in the therapeutic response to drugs metabolized by this enzyme. Differences at gene level may translate into protein level with consequent impairment of the enzyme activity. As a result patients with such genetic differences might experience undesirable effects or no effect at all.