It is a known fact that everyone responds differently to drugs and medicines. Although many individuals respond well and gain the intended effects, others don’t benefit at all.
Similarly, every drug has side effects. Though some individuals are likely to suffer more than others. Your genes partially dictate this difference in drug responses.
Pharmacogenomics, as a subset of personalized medicine, is used to describe the tailoring of medications to a person’s genetic makeup to make sure the right drugs are offered to the right patients on time.
That means patients are likely to derive benefits and less likely to experience some side effects from a certain treatment or medication.
It as well means resources are wisely spent. This is good news for health economists and patients. But pharmacogenomics still has a long way to go and faces a lot of challenges.
The Basics
When studying the reaction of drugs in people, researchers mainly focus on two main determinants. These include how well drugs target cells, like neurons or heart tissue and how much medicines are required in your body.
The scientific terms for the two determinants are pharmacodynamics and pharmacokinetics. Both of them are important considerations when it comes to the pharmacogenomics field.
Pharmacogenomics Testing
This testing identifies whether certain gene variations are present or absent, which may influence the way an individual responds to specific medications.
For instance, if you are diagnosed with breast cancer, you will be scheduled for a biopsy so as to collect tumor tissue as well as know your HER2 status.
Cancer, which is HER2-positive, means there is a positive presence of a certain protein referred to as HER2 (human epidermal growth factor receptor 2). If tests are HER2-negative, it means HER2 protein is absent.
As a patient with HER2-positive cancer, you will be eligible for treatments targeting HER2 protein. That means your medical provider will place you on drugs targeting HER2 receptors and block any chemical signal that stimulates cell growth.
Drug Responses and Heritability
Studies in a family may define the extent of sudden cardiac death or common disease phenotypes, such as sudden myocardial infarction, including heritable components.
But it is normally not possible to accumulate drug-response phenotypes across related patients with a similar disease. Because of that, heritable components of variability in the drug action can’t be defined well.
Resequencing as the Strategy for Improving Pharmacogenomics Studies
This aims to identify causal variants if the SNPs identified in the GWAS are not likely to be functional. One method consists of resequencing chromosomic regions of interest in people representing discordant and concordant phenotype-genotype associations.
Discordant is usually designed in individuals homozygous for rate allele of hit SNP without studying phenotype. On the other hand, discordant is normally defined in individuals homozygous for rare alleles of hit SNP, which presents associated phenotypes.
In a Nutshell!
It is now clear that pharmacogenomics is one of the important determinants of drug response and disposition in humans. It is also clear that you are in the early phases of defining pharmacogenomics determinants, and a broader approach to genomics is required to elucidate determinants for many medications.
Once gene networks governing medicine response in humans are defined, it will be possible to accurately optimize drug therapies, depending on every patient’s capability to respond, transport, and metabolize medications.
