Pharmacogenomics: The Key To Tailored Medical Treatments
When you go to the doctor and get handed a prescription, it feels like it is exactly what you need. It feels like it's special to you… buts it's not it’s a one size fits all prescription.
No two people are the same. But when it comes to medicine as long you have the same symptoms you’ll get handed the exact same prescription.
This is where pharmacogenomics comes in. Pharmacogenomics will make sure that every prescription is fit for you. It’s the key to tailored medicine.
Personalized medicine:
Imagine saying a 6’5” and a 300-pound adult should be wearing the same clothes as a kid. That sounds bizarre right, but for some reason, when it comes to our health care and medicine we find the same thing normal. Two different people with completely different lifestyles can be prescribed the same thing. Except, in this case, it won’t just result in clothes not fitting. Patients can develop serious and even life-threatening symptoms due to the fact that their medicine isn’t personalized to them.
Personalized medicine takes into account the patient’s individual genetic makeup, medical history, lifestyle, and other factors to develop a treatment plan that is fit for the individual. The goal of personalized medicine is to provide the most effective, efficient, and safest care possible. There are many benefits of personalized medicine, including:
1. Increased Effectiveness: By taking into account a patient’s unique genetic makeup, doctors can more accurately target the root cause of a disease or condition. This can lead to more effective treatment and, ultimately, better health outcomes.
2. Fewer Side Effects: Personalized medicine can also help to minimize the risk of side effects from treatment. By targeting the root cause of a disease, personalized medicine can reduce the need for potentially harmful medications or treatments.
3. Improved Quality of Life: Personalized medicine can also improve a patient’s quality of life. By providing more effective and safer treatment, personalized medicine can help patients live longer, healthier, and happier lives.
4. Reduced Costs: In the long run, by allowing doctors to target treatments specifically to each individual patient’s needs, patients’ treatments will be more successful. This means that patients are less likely to experience side effects from treatments, and they won’t require multiple treatments/follow-up treatments.
In America alone, every year 2 million patients develop serious side effects from pharmaceutical drugs and over 100, 000 die because of them. This is because doctors refuse to take into count the fact that we are all different. Literally, not one of us humans is the same and giving us all the same generalized medicine puts us at risk for treatment failure, serious side effects, and more.
When it comes to everyday medicine like prescription medicine. There currently is no way for doctors to give you a personalized prescription/treatment because it’s expensive, inconvenient, and some call it pointless. So there has to be something to fix this and make personalized medicine a part of our everyday life. This is called pharmacogenomics.
Pharmacogenomics is the key to tailored everyday medicine, pharmacogenomics is the study of genes and their effects on medicine. When you are getting a suit tailored, the tailor takes your measurements so the suit that they tailor can truly be a perfect fit. That’s what pharmacogenomics does for medicine.
For example, someone with more MC4R genes will have a higher metabolism rate. Without pharmacogenomics, doctors will have no way of knowing this. So naturally, the doctor would prescribe them the same prescription drug that they would to any patient not knowing that their high metabolism can change the effectiveness of the drug. But not with pharmacogenomics, with pharmacogenomics all we require is a blood test to understand what's needed to help you.
Pharmacogenomics is the study of the genetic factors that influence drug response, by understanding your genes and cells we can understand how you will react to drugs of different sorts. Heres an outline of your cell structure, your DNA, and your genes.
Inside your cells are chromosomes. Chromosomes are made of many long strands of DNA. And your genes are segments of this DNA.
Your DNA is made up of 4 units which are called nucleotides, ACGT; Adenine (A), cytosine (C), guanine (G), and thymine (T).
These nucleotides are what you would call the “basic building blocks” of your DNA. In reality, your gene segments are actually hundreds and thousands of nucleotides long but, this image shows a scale version of the structure of the genes.
Now, this looks like a lot. But it’s simply just strands of DNA which are made up of nucleotides. This section of DNA has a genetic sequence and each of these sequences encodes for a molecular product. In this gene, you can see how they encode for a protein.
In pharmacogenetics, there are two major parts which you study. The first is pharmacokinetics. Pharmacokinetics is the study of how a drug goes through the body and how much of it is needed to reach its target. The second is pharmacodynamics. Pharmacodynamics is the study of the drug’s effect on its target and its surroundings along with how the target responds to the drug.
Pharmacokinetics encompasses four processes; absorption, distribution, metabolism, and excretion.
Absorption → Absorption refers to how the drug enters the bloodstream after which it enters the body. It describes the transportation process of the drug from the entry point to the circulation system. Drugs can be taken as pills, inhalants, injections, and more. A factor of absorption is bioavailability which measures how much of the drug enters circulation.
Distribution → Distribution studies where the drug travels after the absorption process, and how much of this drug actually reaches the target site. After absorption and once the drug is in the bloodstream, it needs to reach the liver for the metabolism process to occur. It then continues in the bloodstream until the target site is reached. Distribution can be a fast or slow process, depending on the person a lot of the drug can reach its target site or some can be lost along the way. The distribution process is never an exact and even thing. Some determining factors include fat, muscle mass, water composition, gender, and where the target site is in your body.
Metabolism → When you eat an apple and it enters your body, metabolism is how that apple is converted into energy and how fast this is done. That’s what the metabolism process does to the drugs. Most drugs travel through the liver during the distribution process. Once in the liver, enzymes such as the P-450 enzyme convert prodrugs to active metabolites or convert active drugs to inactive form. Few drugs such as antidepressants, anticonvulsants, and anesthetics are not metabolized by the liver. Metabolism can be a slow or a fast process based on your body, genes, and how healthy your liver is. Examples of genes which contribute to metabolism are the LEPR, UCP and MC4R genes.
Excursion → Excursion describes how the drug leaves the body after its job is done. Whether this is through urine, exhalation, or another method.
As you can see pharmacokinetics is the study of how drugs travel throughout the body. The drug starts by entering the body and bloodstream (Absorption), then it needs to reach the site (Distribution). The drug needs to be processed and broken down(Metabolism), then finally how it leaves the body(Excursion).
The second factor in pharmacogenetics is pharmacodynamics. Pharmadynamics studies the effects of drugs and the mechanism of their actions. Whether the target is a receptor, ion channel, enzyme, or something else. In pharmacodynamics, you study the biochemical, physiologic, and molecular effects of the drug, along with that it surveys the receptor binding, post-receptor effects, and overall if the drug is successful or not on its target.
Biochemical effects → Biochemical effects refer to the impact the drug has on the biochemical pathways. Biochemical pathways are also known as metabolic pathways, these are step-by-step series of interconnected biochemical reactions. In biochemical pathways, each step is catalyzed by an enzyme. Biochemical pathways lead to a certain product or change in the cell, and drugs can have an effect on this.
Physiologic effects → Physiologic effects refer to the effect the drug has on your body, kind of like the side effects of the drugs. The drug could affect parts of your body such as your hands, legs, and feet. It can also affect the circulatory system and other systems, overall physiologic effects are unwanted effects that the drug causes. Your physiologic effects can be determined by the structure of the drug and your body.
Molecular effect → Your body is made up of cells and these cells are made up of molecules. The molecular effect of drugs refers to the effect the drug has on your cells and molecules. That could be there is no effect or that the drug infects or kills some of your cells. For example, certain medicines target your cells, specifically the infected ones which are causing you harm.
Receptor binding process and post-receptor effects →Pharmacodynamics studies the receptor binding process effects along with the post-receptor effects. Once a drug reaches its target it binds to and activates a receptor. A receptor is a protein molecule which is either on or in a cell. Its role is to bind to specific substances and cause an effect in the cell. Once the drug binds to and activates a receptor it then causes an alteration to intercellular messengers/proteins (effectors).
The effectors’ purpose as a molecule is that once it receives this chemical signal it can go and alter cell structure and functions. Meaning it can alter infected cells that carry things such as the diseases and toxins which the drug is targeting. Along with that, it can trigger cells’ defence response to fight diseases. Studying the receptor binding process and the post-receptor effects and ensuring that it is successful is a very important part of pharmacodynamics.
Personalized medicine can furthermore improve the cancer world. Chemotherapy (the leading cancer treatment) currently only has a 41.8 success rate. Versus personalized cancer treatments which have been around for a shorter time have already shown more hope and higher success rates.
Though pharmacogenomics seems like an amazing thing there are ethical and financial issues that occur with pharmacogenomics. The Genetic Information Nondiscrimination Act (GINA) was passed by Congress to protect Americans from genetic discrimination. This focuses on preventing genetic discrimination between patients and doctors. It states that it is illegal to require genetic testing for patients. This prohibits insurance companies from using genetic information to adjust premiums, deny coverage or impose restrictions that relate to preexisting conditions. This law and its purpose are why certain experts are raising ethical questions. Financial issues refer to the fact that since personalized medicine is a new approach to treatments it will be more expensive than normal treatments which have been around for much longer.
But overcoming these ethical and financial problems will allow personalized medicine to reach its full and amazing potential. Pharmacogenomics should be a testing option for every patient when being prescribed medicines. With this when you get handed your prescription you’ll feel special knowing that it’s a perfect fit for you!
