Who knew that feeling pain and a sense of smell worked the same way in your brain? A new study published in Nature finds that people who feel no pain due to a genetic disorder also have no sense of smell. This study shows that the protein used to transmit information regarding pain and odor are the same. Researchers tested this theory on three people who have a mutation in the SCN9A gene and cannot feel pain. These people have all broken bones and two of them have given birth painlessly. During the study, none of these people could distinguish scents such as balsamic vinegar, orange, mint, coffee or perfume from water. Interestingly, none of these people were even aware that they lacked a sense of smell because it was a genetic defect from birth; therefore they do not even know what they are missing. Up until this study, scientists were unaware of the fact that pain and smell shared a common communication pathway.
In this finding, it was discovered that odor-detecting nerve cells have the same sodium channels at the tips of their axons used to send electrical signals to the brain. People with SCN9A mutations lack the sodium channel, therefore messages sent by pain or scent nerves never make their way to the brain, and therefore are never “felt.”
Although lacking a sense of smell did not bother the lifestyle of the participants of this study, the same could not be said for lab mice. Mice engineered to lack the same sodium channel used for smell were quite bothered by this disadvantage. Baby mice are born blind and therefore use their sense of smell to navigate their way to their mother’s milk. As a result, these baby mice were underweight and mother mice could not locate babies that wandered from the nest. Adult mice also experienced this disadvantage as they wandered into territory marked by the scent of foxes.
Pharmaceutical companies have already been fabricating pain killing drugs that interfere with sodium channels; however this new study has them rethinking its side effect of eliminating smell. Because odor is a part of cooking and experiencing the flavor of food, it has been discussed that a lack of smell would also result in a lack of taste. Would you give up your sense of smell and taste for a pain-free life?
To read more about this study please visit the following website: http://www.sciencenews.org/view/generic/id/71582/title/Who_felt_it_not%2C_smelt_it_not
Written by: Melissa Marques