Genetic Polymorphism

Genetic Polymorphism describes variations in DNA sequences occurring within populations at frequencies greater than 1%, including single nucleotide polymorphisms representing individual base changes, insertions, deletions, or structural variants affecting gene function, expression levels, or protein structures. These common genetic differences contribute to phenotypic diversity and critically for pharmacology, drug metabolism rates and treatment responses.

The pharmaceutical industry extensively studies genetic polymorphisms throughout development addressing pharmacogenomics, patient stratification, and personalised medicine strategies. Polymorphisms in drug-metabolising enzymes like cytochrome P450 isoforms profoundly affect drug exposure, with poor metabolisers experiencing elevated concentrations and potential toxicity while ultra-rapid metabolisers show insufficient efficacy. HLA polymorphisms associate with immune-mediated adverse reactions, enabling screening preventing hypersensitivity reactions. Clinical trial design incorporates polymorphism considerations through genotype stratification and pharmacogenomic substudies. As whole-genome sequencing becomes routine and precision medicine advances, genetic polymorphism characterisation increasingly informs development strategies and personalised treatment approaches.