Effect of the rs2590498 (A/G) Polymorphism of the OBPIIa Gene on the Olfactory Threshold and Perception Intensity of Fatty Acids

The perception of the odor of fatty acids provides individuals with information about the nutritional content of foods. This perception varies depending on biological and genetic factors. Previous studies have shown that odorant binding proteins (OBPs) present in olfactory mucus play an important role in capturing and transporting odorants, typically lipophilic molecules, through the mucus to the olfactory receptors (ORs). The main objective of this research was to study the role of the rs2590498 (A/G) polymorphism of the human OBPIIa gene on the threshold and intensity of odor perception of palmitic (PA), oleic (OA) and linoleic (LA) acids. Volunteers were genotyped for OBP polymorphisms and classified as normosmic or hyposmic based on their threshold for n-butanol. The results show that normosmic or AA genotype participants perceived the odors of PA, OA, and LA at lower concentrations and with greater intensity than hyposmic or AG/GG genotype participants. Furthermore, the perception intensity reported by participants showed the following decreasing order: LA > OA > PA. These findings indicate that the intensity and threshold of perception depend on the lipophilicity of the molecule. These results indicate that genetic and biological factors, as well as the chemical properties of the molecules, play a key role in the olfactory perception of fatty acids.