Sign in Subscribe
Antidepressants

Genetic Polymorphisms Influence Antidepressant Responses in South Indian Psychiatric Patients

Strategic Insights

— 1 min read

A study published in the Annals of Neurosciences has shed light on the role of genetic polymorphisms in shaping individual responses to antidepressant medications. The research, conducted by a team of scientists at the Advanced Center for Treatment in India, found that variations in the cytochrome P450 enzyme, particularly the *2 allele, significantly affect drug metabolism and efficacy in South Indian psychiatric patients.

The study, which involved 140 participants, revealed that nearly 28% of the population carried the *2 allele, leading to reduced enzyme activity and a higher risk of adverse reactions. The findings highlight the importance of pre-emptive pharmacogenetic testing to guide antidepressant selection and dosing in this population, advocating for the implementation of precision psychiatry in routine mental health care.

Key Takeaways:

  • The study found that genetic polymorphisms significantly influence individual responses to antidepressant medications in South Indian psychiatric patients.
  • The cytochrome P450 enzyme, particularly the *2 allele, affects drug metabolism, leading to both efficacy and safety implications.
  • A substantial proportion of South Indian psychiatric patients (44.3%) exhibit reduced enzyme activity due to the presence of the *2 allele.
  • The prevalence of the *2 allele is higher in South Indian psychiatric patients (27.5%), contributing to reduced enzyme activity.
  • The study concludes that pre-emptive pharmacogenetic testing is essential for guiding antidepressant selection and dosing in this population, supporting the implementation of precision psychiatry.
  • The study involved 140 psychiatric patients of South Indian ancestry across two tertiary psychiatric centers.
  • Genomic DNA was extracted from peripheral blood samples and genotyped for the (681G A) variant using TaqMan-based real-time PCR.
  • Participants were categorized into metabolizer phenotypes based on CPIC guidelines, with normal (*1/*1), intermediate (*1/*2), and poor (*2/*2) metabolizers.

Statistics:

  • 27.5% of participants carried the *2 allele.
  • 55.7% of participants exhibited normal metabolizer phenotype (*1/*1).
  • 33.6% of participants exhibited intermediate metabolizer phenotype (*1/*2).
  • 10.7% of participants exhibited poor metabolizer phenotype (*2/*2).
  • 44.3% of patients were classified as non-normal metabolizers (intermediate or poor).
  • The allele frequency did not deviate significantly from Hardy-Weinberg equilibrium (p = 0.0614).

Sources:

  • Prevalence of CYP2C19 Poor Metabolisers Among South Indian Psychiatric Patients: A Pharmacogenetic Perspective Toward Precision Psychopharmacology. Annals of Neurosciences, 2025:09727531251379157.
  • NewsRx. Findings in Psychopharmacology Reported from Advanced Center for Treatment (Prevalence of CYP2C19 Poor Metabolisers Among South Indian Psychiatric Patients: A Pharmacogenetic Perspective Toward Precision Psychopharmacology). Mental Health Weekly Digest. October 20, 2025; p 324.

Read more