This article by Deborah Parker Wong on research into the genetic basis of olfactory sensation is interesting in its own right but especially important for wine.
The study looked at the capacity of 12,000 test subjects in Iceland to identify and rate for intensity and pleasantness 6 odors: fish, licorice, cinnamon, lemon, peppermint, and banana. They then analyzed the olfactory genes of the participants.
They discovered that variations in the intensity and ability of participants to identify licorice, cinnamon, and fish were correlated with genetic variations.
People with an increased sensitivity to trans-anethole—a compound found in black-licorice products as well as botanicals such as anise seed, star anise, and fennel—carry a gene that makes licorice odors more intense, more pleasant, and easier to name accurately. (Other studies have found this predisposition to be much more common in East Asians than it is in Europeans.) The genetic variation for cinnamon, meanwhile, influences the perception of trans-cinnamaldehyde, the major ingredient in both Chinese and Ceylon cinnamon.
Subjects with that variation for cinnamon found it more intense and easier to name.
Even the disposition to identify and enjoy Iceland’s famously disgusting national dish, fermented shark, was subject to gene variation. Some found it neutral or pleasant, describing it as rose, potato, ketchup, or caramel. If we can’t agree about kæstur hákar what hope is there to agree on the aromas of a Cabernet?
The conclusion of the study is that genetic variation enhances olfactory ability.
The implication I draw from this is that, if variations in olfactory genes are adaptive, enhancing survival by improving olfactory ability, then it’s likely there are massive genetic variations influencing olfaction in the human population. (I don’t have access to the research so I can’t determine how widespread these variations were.)
This research tends to indicate that the descriptive accuracy of any tasting note will likely be limited to one person—the person writing the note.
The question is what conclusions should we draw from this regarding wine tasting.
Despite this apparent genetic diversity, some people become expert at wine tasting and can pass rigorous tasting exams. That indicates that some of these capacities can be shaped through education and practice. The jury is still out on that but, if true, there is still a basis for some degree of objectivity in aroma detection. On the other hand, the process of winnowing out people who can’t pass wine tasting exams may just be selecting for people who have the right genes for detecting wine aromas.
At any rate, most people will not have had this training and for them some tasting notes will be misleading. This is just more evidence that a list of aromas is just not a good indicator of what it is like to experience a wine. Texture, mouthfeel and the energetics of a wine are more important.