The Indian Council for Medical Research (ICMR) will soon begin research in the field of pharmacogenomics with focus on identification of genes and pathways involved in pharmacokinetics and pharmacodynamics of drugs, particularly of common drugs. It will also focus on identification of genes/biomarkers associated with variation in efficacy and safety of drugs in Indian populations, particularly of common conditions such as epilepsy, bronchial asthma, ?hypertension, ?hypercholesterole mia/dyslipidemia, ?rheumatoid arthritis, ?cancer, ?diabetes, ?psychiatric disorders and ?infective disorders.
Senior ICMR scientists said that research in this field is significant as genetic variation can affect drug absorption, distribution, metabolism and elimination (pharmacokinetics) as well as drug action (pharmacodynamics). Incorporation of pharmacogenomics into clinical drug development offers a unique opportunity for pharmaceutical companies to enhance efficiency and success of drug development.
Scientists say that the safety and efficacy of drug treatment is highly variable. The variation could be due to several factors including age, gender, nutrition, host’s health and disease status and also genetic background of the patients. The latter in some cases may be quite significant, even leading to post-marketing drug withdrawal, emphasizing the necessity of pharmacogenetic studies.
With availability of human genome sequence it is now possible to expedite identification of drug response-determining genetic variants with greater ease. Current estimates indicate a frequency of 1 SNP per 300 base pairs, and 1 per 1000 base pairs in coding regions, making SNPs a powerful tool to establish a link between genetic variability in drug response (as well as susceptibility to disease), the scientists said.
Anticipating their usefulness in disease and health management, an international SNP Consortium has been formed for discovery and creation of high density SNP maps. It needs to be extended to Indian populations as well. These maps will help in large-scale association studies to locate genes correlated with responsiveness and side effects to drugs, vaccines, toxins and xenobiotics etc.
As an off-shoot of ICMR’s initiative on genomics and molecular medicine, a task force on pharmacogenomics has been initiated to encourage research in this field. The task force has invited proposals from scientists and clinicians working at various universities and medical colleges, and DSIR-recognized institutions in the country to begin research in the field of pharmacogenomics.
The study will also focus on validation of human SNP/CNV sentinel haplotypes of identified genes in Indian populations (various geo-ethnic groups), preferably in a multi-centric approach; development of Indian pharmacogenomics-chip based on HAPMAP SNPs validated in Indian populations; genes involved in variation in immunological response to vaccines in Indian populations; and genes involved in variation in response to toxins/xenobiotics/nutrients in Indian populations.