Have you ever wondered why some people seem to get more pain relief with opioid medications than others? Scientists at the University of North Carolina at Chapel Hill's Center for Neurosensory Disorders may have discovered the answer. They have identified genetic variations that have given them insight into why individuals repsond differently to opioids like morphine.
There's a wide range of differences in how patients respond to opioids. One patient may experience more than 10 times the amount of pain relief as another patient receiving the same dosage. And as many as one-third report significant side effects. Until now scientists have not known why there is such a drastic difference in response.
This study, published in the March 15, 2009 issue of the journal Human Molecular Genetics may hold the key that unlocks the mystery. Researchers identified new variations in the gene that produces opioid receptors. Opioids work by binding to these receptors in the brain and spinal column, which then slows the rate at which a pain message can be transmitted. The genetic variations found in these receptors play a crucial role in determining how a patient will respond to opioid medication.
Although this is just the first step on the journey, researchers are hopeful that these findings will lead to the development of:
• Genetic tests that will predict how an individual patient will respond to a particular pain medication.
• Medications (possibly a new class of opioids) that offer greater pain relief with fewer side effects.
Source: Shabalina, Svetlana A., et al (2009, March 15). Expansion of the human mu-opioid receptor gene architecture: novel functional variants. Human Molecular Genetics, Vol. 18, No. 6.
Published On: April 30, 2009