Pharmacogenetics: Genetic Testing for Personalized Medical Treatment
The more we learn about genetics, the better able we are to impact a myriad of health conditions through personalized medical treatment. The unique tailoring of customized therapies to a person’s own genetic profile enables improved outcomes with a reduced need for trial and error. If we can know in advance how a particular medication will work for each individual, we can alter the treatment or dosage prescribed to meet the patient’s needs. This is no longer the science fiction depicted in movies and television, but a reality that is beginning to play out in medical centers and hospitals across the country – and with the potential for improved levels of care for children.
This new field – pharmacogenetics – is the study of how a person’s genes affect the response to various medications. DNA will show how each individual metabolizes drugs to provide a custom-tailored approach to treating a condition. Knowing how a drug will be absorbed and metabolized can eliminate the lengthy time it takes to find the right treatment for each person.
One of the best aspects of this testing is that it does not require a needle to draw blood. A quick swap of the inside of the cheek is all that is needed to make this determination. This is especially useful for children who often have a fear of needles. Since the liver plays a role in the metabolization of many medications, being able to avoid adverse liver reactions is one more positive aspect associated with this testing.
Pharmacogenetics looks at genes for variances in proteins that affect medication responses. This can include liver enzymes responsible for converting drugs into their active or inactive forms. A small difference in a genetic sequence can impact how a medication performs or whether there will be adverse reactions. The liver enzyme CYP2D6 is a prime example for this scenario as it acts on one-fourth of all prescription medications. Most people have two copies of each gene, but some have hundreds or thousands of copies of CYP2D6. This can result in the rapid metabolization of a drug. For example, CYP2D6 converts the painkiller codeine into morphine, and a person with extra copies will convert codeine to morphine at such a rapid rate that even a standard dose can result in an overdose of medication.
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