Medications do not affect everyone in the same way. Some people experience side effects, while others do not achieve the desired treatment outcome. Scientists and doctors from the University of Tartu found that the interaction of drugs and genes may be the reason.
The researchers studied two important liver enzymes: CYP2C19 and CYP2D6. These enzymes metabolize approximately 40% of drugs. The study found that people missing a DNA segment in the CYP2C19 gene metabolize drugs more slowly. This can lead to drug accumulation in the body and increase the risk of side effects.
Pharmacogenomics researcher Kristi Krebs explained that normally, the drug concentration in the body decreases after absorption. However, this often does not happen in people with CYP2C19 gene problems. The drug may accumulate in the body, which may worsen treatment outcomes or increase the risk of side effects.
A genetic test alone is not sufficient. The study showed that non-genetic factors also influence drug metabolism. For example, the simultaneous use of different medications, diseases, and lifestyle can affect it.
The study revealed that the combined use of drugs can slow down their metabolism even in people with a normal genetic profile. This means that even people with the same genes can experience different drug effects.
The study involved 114 gene donors. They were given small doses of two drugs: omeprazole and metoprolol. The drug concentrations in the blood were measured at ten time points, allowing accurate assessment of enzyme activity.
According to Lili Milani, head of the Estonian Biobank, the study was possible thanks to the dedication of gene donors. The aim of the study was to understand how genetic variants affect drug metabolism in the body.
The scientists hope that the study results will help in more precise drug prescription and reducing the risk of side effects in the future. Gene donors can familiarize themselves with their CYP2C19 gene activity on the Minu Geenivaramu portal.
Changes to the treatment regimen should always be made in collaboration with a doctor. The study results were also introduced to pharmacogenetic test providers in Estonia.