Reconstructing the pharmacogenomic landscape of psychiatric medication metabolism in the Indian population

With the advent of genomic technologies, pharmacogenomics has evolved significantly. Such advancement facilitates comprehensive identification of common and rare alleles crucial for psychiatry treatments, especially in context of Indian psychiatric patients who are genetically diverse and for whom data is limited.

This study explores the pharmacogenomic spectrum of CYP2C19, CYP2D6, and CYP2C9 genes in an Indian psychiatric cohort of 383 individuals (264 patients, 119 controls) using Axiom PMD Array.

Beyond common phenotypes like CYP2C19 *1/*2, we identified rare functional phenotypes including CYP2C19 *1/*34, CYP2C9 *1/*11 and CYP2D6 *4/*5 that are frequently overlooked in regular screenings. Interestingly, 3% of individuals were identified as most likely non-responders to medications metabolized by these three enzymes, suggesting the importance of platforms that cover both common and rare alleles in populations with high diversity. The study observed 13.26% poor CYP2C19 metabolizers, 2.27% poor CYP2D6 metabolizers, and 3.41% poor CYP2C9 metabolizers in the psychiatric cohort.

The study identifies three percent of the cohort shows compromised metabolism across all three genes, emphasizing that comprehensive screening of common along with rare functional variants is essential for personalized psychiatric treatment in India.