How about getting to know the effects of the pill that you are going to pop in?
With the recent advances in personalized medicine, it is possible to tailor the drug to suit your disease needs, with practically nil adverse effects. The effects of medication are influenced by many factors such as diet, environment, health, etc. However the effect of genes cannot be ruled out completely.
Pharmacogenetics deals with inherited variations in the effect of drugs. It tries to find out how the individual's genetic make up determines the efficacy and toxicity of the drug molecule.
1. Can get drugs which are more effective and safe.
2. Prediction of dose requirements based on more effective parameters
3. Improved methods of identification of diseases.
4. Prevention of diseases.
Imagine a drug being given to a population of patients. The entire population will not respond to the drug molecule in the same way. There can be groups of patients who get benefited from the drug while others may fail to respond to the drug itself. Similarly some individuals may exhibit adverse reactions while others show none of these effects.
Pharmacogenetics studies these diverse responses to drug effects and explores the genetic mutations or variations underlying such responses.
The genotype is characterized to the genomic DNA. The influence of any variation of DNA sequence on pharmacokinetic parameters of the drug, receptor binding functions etc is analyzed. Advanced techniques are used for quantifying the metabolites, and undertake clinical investigations. Eg: receptor density is calculated through PET methods.
The differential effects of a drug are analyzed by in-vivo studies in different patients. The response is measured as variation in biological parameters which are due to inherited gene variants.
The method has been in use for finding receptor binding efficiency and to find out the dose requirements. For example, genotyping and phenotyping tests are used to determine the initial dose determination and the choice of antidepressants.
With the recent advances in sequencing techniques, the pharmacogenetics studies have taken a quantum leap into a new field, Pharmacogenomics. It is the study of the effects of drugs and responses in the context of the entire genome of the individual. With this, the researchers will have a wider approach and is possible to analyze the variations in all the genes of a group of individuals.
Pharmacogenomic studies involve systematic identification of all human genes and gene products. The genetic variations in humans are analyzed along with the changes in gene and/or protein expression profiles over a period of time under healthy and diseased conditions.
This takes another step in pharmacogenomics to the prescription of drugs and determination of appropriate dosage to the patients. The information from the pharmacogenomic studies is processes to decide the drugs by doctors.
This can be done by preprogrammed algorithms of decision making which helps the doctors to determine the course of treatment.
Decision support systems shortly called DSS are aimed to improve the decision making process of treatment with the data like disease history, predisposing factors and the genetic make up of the individual.
With such tailored strategies in prevention, treatment and management approaches to diseases, it is possible to efficiently reduce the risks. More precisely risk stratification can be done better.
Areas of personalized medicine
The major applications are in the field of diagnostics and treatment.
• The application of pharmacogenetic knowledge such as pharmacokinetics, pharmacodynamics, molecular and cellular functional assays can determine the individual's risk to develop a particular disease or condition.
• It can help the practitioners to suggest alternative lifestyles or medicines to combat or minimize the risk.
• Dosage of the drug can be prespecified based on the metabolic rate. Some patients are slow metabolizers while others metabolize the drug rapidly.
• The effectiveness of the standard treatment can be predicted beforehand.
• It can also be used to monitor the efficiency of the current treatment and decisions for changing or continuing the treatment strategy can be based on such knowledge.
• Lastly, the clinical treatment methods can be improved or tailored to suit the individual. It will reduce considerable time, cost and risk involved in conducting clinical trials.
• It is also possible to divide the entire population into subpopulations for improved patient access and can considerably reduce the drop out rate in trials.
The approach has already been tried and tested in several disease conditions such as cardiovascular disorders, cancer and HIV.
About Author / Additional Info: