Final answer:
CYP2C19 *1 refers to a specific allele of the cytochrome P450 2C19 enzyme, which is significant in pharmacogenomics. The star and number indicate the allele variant that affects drug metabolism and influences a drug's efficacy and toxicity.
Step-by-step explanation:
The CYP2C19 *1 (CYP2C19) notation refers to a specific allele of the cytochrome P450 2C19 enzyme. The star (*) and following number represent the allele variant of the gene. This designation is critical in the field of pharmacogenomics because it relates to how different individuals metabolize drugs. Certain alleles, such as those of the CYP2C19 gene, have high polymorphism in the human population, influencing drug efficacy and toxicity due to variations in metabolic rate.
In relation to drug development, understanding these genetic variations is crucial. For example, pro-drugs that are metabolically activated by enzymes with high polymorphism might require alteration to ensure efficacy across diverse populations. Additionally, identifying the relative contributions of each CYP isoform to hepatic drug clearance is important to predict drug behavior in the body.