The most prevalent poor metabolizers (PM) variant genotypes of CYP2C19 are  Blank 1 Question 2 and  Blank 2 Question 2 in Asian

The most prevalent poor metabolizer (PM) variant genotypes of CYP2C19 in Asian populations are CYP2C19*2 and CYP2C19*3.

CYP2C19 is a key enzyme in drug metabolism, particularly for various antidepressants, proton pump inhibitors, and antiplatelet drugs. Genetic variations, specifically polymorphisms within the CYP2C19 gene, can significantly influence how individuals metabolize certain drugs.

The CYP2C192 variant is characterized by a single nucleotide polymorphism (SNP) that results in a splice site defect, leading to a nonfunctional enzyme. The CYP2C193 variant results in a premature stop codon, further disabling the enzyme's activity.

In Asian populations, these variants are more commonly found, contributing to a higher prevalence of poor metabolizer status, which can affect drug efficacy and safety. Consequently, understanding one’s CYP2C19 genotype is critical for personalized medicine and optimized pharmacotherapy, especially in the context of medications that are heavily reliant on CYP2C19 for metabolism.

It's essential for healthcare providers to consider these genetic factors when prescribing medications to individuals of Asian descent to minimize adverse effects and enhance therapeutic outcomes.