Trans-3-methyl-2-hexenoic acid is considered one of the most pungent compounds in underarm sweat. Galaxolide is a synthetic musk often described as having a floral, woody odor that’s used in perfumes and cosmetics, but also things like kitty litter. The research team was able to identify olfactory receptor variants for those odors. In the case of the underarm odor, most people with the more evolutionarily recent gene variant found it more intense. The opposite was true for galaxolide.
— Read more in Body Odor May Smell Worse to You Than Your Ancient Ancestors at The New York Times, or see From musk to body odor: Decoding olfaction through genetic variation at PLOS Genetics.