Genetic Polymorphism

Pharmacogenomics, an interdisciplinary basis of personalized medicine, explains the influence of genomic variation on drug disposition, response, and toxicity. Pharmacogenomics is exemplified in both mechanistic and clinical concepts, demarcating its crossing point between pharmaceutical and biomedical sciences. Polymorphisms in drug-metabolizing enzymes (e.g., CYP2D6, CYP2C9, CYP2C19), transporters (e.g., ABCB1, SLCO1B1), and pharmacologic targets (e.g., VKORC1, EGFR) alter pharmacokinetic and pharmacodynamic profiles, making justifications for individualized therapeutic strategies. The paper defines the pharmacogenomic uses in oncology, cardiology, and psychiatry fields for which pharmacogenomic markers (e.g., HER2, KRAS, CYP2C19) are now a requirement to maximize the effect of treatment and minimize drug reactions. The review also points towards the pivotal role of allied biomedical sciences—i.e., human physiology, clinical biochemistry, and molecular diagnostics to locating gene–drug interactions within the frame of everyday clinical phenotypes. Despite the great leaps, clinical translation remains beset by issues such as fragmentation of regulation, bioethics, population-specific gaps in data, and a lack of clinical genomic literacy. Technologies in the form of next-generation sequencing, multi-omics fusion, and artificial intelligence-based decision support systems, however, offer the potential for scalable and equitable deployment. In summary, pharmacogenomics is a paradigm shift towards genotype-directed pharmacotherapy. For its successful incorporation in clinical medicine, interdisciplinary collaboration, strong informatics support, and harmonized regulatory policies need to supply rational, safe, and personalized drug therapy.

Alleles A1 and A2 of the Bos taurus CSN2 gene are the most common in a number of dairy cattle breeds. A genetic variant of the bovine β-casein gene includes A1 and B which encodes a histidine residue at codon 67, resulting in potential liberation of a bioactive peptide, β-casomorphin, upon digestion. This is an opium family substance, and has been associated with a large number of clinical implications in humans. Study includes amplification of bovine β-casein gene and further differentiation of variants A1 and A2 beta casein in cows. Conventional PCR was done to amplify β-casein gene in three hundred and one specimens. Further eighty amplicons were sent for sequencing. From the sequenced data, 24 were A2 homozygous (A2A2), 11were A1 homozygous (A1A1) and 37 heterozygous (A1A2). Allele discrimination in cows will be significant for the farmers, breeding programmes as well as for dairy industries as the milk variant determination will predict the outcome of the beta casein variants which are of utmost clinical relevance.