Journal of Advanced Pharmaceutical Technology & Research

LETTER TO THE EDITOR
Year
: 2010  |  Volume : 1  |  Issue : 4  |  Page : 423--424

Pharmacogenetics: The future medicine


Rajiv Saini1, Santosh Saini2, RS Sugandha3,  
1 Department of Periodontology, Oral Implantology, Rural Dental College, Rural Medical College, Loni, Maharashtra, India
2 Department of Microbiology, Rural Dental College, Rural Medical College, Loni, Maharashtra, India
3 Department of Prosthodontics, Rural Dental College, Rural Medical College, Loni, Maharashtra, India

Correspondence Address:
Rajiv Saini
Department of Periodontology & Oral Implantology, Rural Dental College, Loni, Tehsil Rahata, District Ahmednagar, Maharashtra 413 736
India




How to cite this article:
Saini R, Saini S, Sugandha R S. Pharmacogenetics: The future medicine.J Adv Pharm Technol Res 2010;1:423-424


How to cite this URL:
Saini R, Saini S, Sugandha R S. Pharmacogenetics: The future medicine. J Adv Pharm Technol Res [serial online] 2010 [cited 2020 Nov 29 ];1:423-424
Available from: https://www.japtr.org/text.asp?2010/1/4/423/76443


Full Text

Sir,

As early as 1958 the German pediatrician Friedrich Vogel suspected that our genes play an important role in determining our response to drugs and proposed a name for the branch of science that investigates this phenomenon, i.e. pharmacogenetics. Pharmacogenetics is the science that underpins understanding the role that an individual's genetic make-up plays in how well a medicine works, as well as what side effects are likely to occur, improving our ability to identify the genetic causes of diseases and search for new drug targets, while pharmacogenomics is the broader application of genomic technologies to new drug discovery and further characterization of older drugs. Pharmacogenetics refers to genetic differences in metabolic pathways which can affect individual responses to drugs, both in terms of therapeutic effect as well as adverse effects. Pharmacogenomics is a rapidly developing field that has important implications in individualized treatment for patients and its implication affect drug development issues such as drug safety, productivity, and personalized health care. Pharmacogenomics combines conventional pharmaceutical sciences such as biochemistry with annotated acquaintance of genes, proteins, and single nucleotide polymorphisms. The benefits of pharmacogenetics or pharmacogenomics includes superior safer drugs, appropriate dosage of drugs, powerful medicines, better vaccination, advance screening of drugs, and reduction in overall cost and treatment in health setup. Genetics may influence choice of medicine in several different ways. People are known to differ in the genetic variants they possess of a series of enzymes concerned with the absorption, metabolism, and excretion of medicines; these are characteristics with which a person is born. They do not necessarily influence susceptibility to disease, but rather the way the individual body processes medicines to which it is exposed. They often affect classes of medicines rather than specific individual medicines. People with particular genotypes may find some medicines ineffective, or may need higher or lower doses in order to achieve a therapeutic effect because they break the substances down either more or less rapidly. There are a large but finite number of these systems for processing medicines, and as our understanding of them advances, predictive genetic testing may be used to determine which medicines to prescribe and in what doses. The field of pharmacogenetics began with a focus on drug metabolism, but it has been extended to encompass the full spectrum of drug disposition, including a growing list of transporters that influence drug absorption, distribution, and excretion. The potential is enormous for pharmacogenomics to yield a powerful set of molecular diagnostic methods that will become routine tools with which clinicians will select medications and drug doses for individual patients. A patient's genotype needs to be determined only once for any given gene, because except for rare somatic mutations, it does not change. Genotyping methods are improving so rapidly that it will soon be simple to test for thousands of single-nucleotide polymorphisms in one assay. It may be possible to collect a single blood sample from a patient, submit a small aliquot for analysis of a panel of genotypes, and test for those that are important determinants of drug disposition and effects. In our opinion, genotyping results will be of greatest clinical value if they are reported and interpreted according to the patient's diagnosis and recommended treatment options. The determination of variation in DNA sequences by the DNA microarray represents the other approach for determining the genetic blueprint underlying the predisposition to complex disease. The combination of these two approaches allows establishing the correlation between the phenotype and the genotype that may be instrumental for pharmacogenomic studies aiming to implement a personalized medicine and provide the pharmacological industry with new and more effective targets for drug development. [1] Genes may also determine how many of the receptors are produced on or within cells and genetic variation may mean that some people produce more of these sites than others and research on the intersection between genetics, genomics, and drug development, and some are already beginning to take genomic variation into account in their drug development pipelines. Post-genomic biomarkers are now playing a critical role in making a prediction of transfer from preclinical to clinical development of drugs in terms of both safety and efficacy. [2] Pharmacogenomics will allow us to identify genes with the highest likelihood of predicting efficacy for novel therapeutics and permit clinical trials to be substantially reduced in size. The ability to classify diseases into distinct molecular subcategories challenges traditional pharmaceutical business economic models of 'one-size- fits-all' drugs, i.e. blockbuster drugs, by aiding in identifying patients for whom the drugs will be both safe and effective. Pharmacogenomics could enhance the value of currently approved drugs with limited market share due to significant side effects or limited efficacy, thus, the economic rationale for personalized medicine-driven healthcare decisions will be based increasingly on the cost savings realized through preventive interventions. [3] The limitations to this potential field includes that many genes are likely to be involved in how someone reacts to a drug, making targeting different drugs very complex, identification of the small variations in everyone's genes that may influence drug metabolism or how the condition develops is very difficult and time consuming and the interactions with other drugs and environmental factors will need to be determined before any conclusions are made about the genetic influence on how the drug is working. Ethical issues includes that the personalized medicine is likely to be very expensive and may adversely impact on equity and access to drugs. Development of drugs will be targeted to those that work well with certain population groups; any such targeting will need to be carefully implemented to avoid a perception of stigma based on ethnicity; the assumption that an individual's race can indicate their genetic profile for drug response is itself problematic since not all people who belong to a particular ethnic group will have the same genetic variations. Clinically, application of pharmacogenetics includes such as the field covers a vast area including basic drug discovery research, the genetic basis of pharmacokinetics and pharmacodynamics, new drug development, patient genetic testing, and clinical patient management. Ultimately, the goal of pharmacogenetics is to predict patient's genetic response to a specific drug as a means of delivering the best possible medical treatment. By predicting the drug response of an individual, it will be possible to increase the success of therapies and reduce the incidence of adverse side effects. [4]

References

1Meloni R, Khalfallah O, Biguet NF. DNA microarrays and pharmacogenomics. Pharmacol Res 2004;49:303-8.
2Ozdemir V, Williams-Jones B, Cooper DM, Someya T, Godard B. Mapping translational research in personalized therapeutics: From molecular markers to health policy. Pharmacogenomics 2007;8:177-85.
3Ahn C. Pharmacogenomics in drug discovery and development. Genom Informat 2007;5:41-5.
4Spear BB, Heath-Chioozi M, Huff J. Clinical application of pharmacogenetics. Trends Mol Med 2001;5:201-4.