In 1991, Columbia University researchers Linda Buck and Richard Axel stunned the scientific world by announcing the discovery of the genes that create the odor receptor proteins in our nose. The repercussions of that major discovery continue to be felt today. The most immediate effect is on olfactory research: it changes how scientists conceive of the physical mechanism of odor detection. Next, the discovery changes our view of higher levels of information processing in the brain. Finally, Buck and Axel’s finding promises to change forever the way the fragrance industry approaches the art and science of perfumery.
The Nasal Genotype: A Diversity of Odor Receptor Molecules
The most dramatic aspect of Buck and AxeI’s work was that it solved a very old scientific probiem concerning the physical nature of odor detection. The primay sensory neurons in the nose are thought to make contact with odor molecules by means of protein receptor structures located in the cell membrane. Activation of these putative receptors by odor molecules of an appropriate size, shape and charge leads to the opening of ion channels in the cell membrane, and ultimately, to the production of a nerve impulse. The question that has long challenged researchers is: does the olfactory system use a few receptor types to recognize many odor molecules, or does it make use of many receptor types? The definitive answer there is a large and diverse multigene family of receptor proteins. There may be as many as 1000 different receptors in action in the human nose.