In short, there are, to put it in Rumsfeld-ian terms, a lot of unknown unknowns here. Just look at my experience. Based on my reaction to the PROP strip, Wysocki concluded that I was a very sensitive taster and possibly a supertaster. When I described my various taste preferences to Bartoshuk and Hanni, both said I was likely a supertaster. My fungiform papillae count was consistent with my being a medium taster. Then the genotyping pegged me as a nontaster. (So how did I detect the PROP? Reed mentioned one possibility: It is believed that another receptor, TAS2R21, may be related to PROP sensitivity alone, and she said it's conceivable that I have a dominant allele for that.) Like a cartoon road sign, my tongue anatomy, my DNA, and my preferences all seem to point in different directions.
Beyond all this, we know that the nose wields much more influence over our flavor perceptions than the tongue. And beyond all that, we know that our gustatory preferences are determined by a wide variety of factors, most of which have nothing to do with our physiological attributes. The key distinction here is between perceptions and preferences. We may be hard-wired to receive flavor stimuli in a certain way, but that information is immediately relayed to the brain, where it is processed through a variety of filters unrelated to our biological dispositions. Our preferences are formed mostly by experience, expectations, culture, and other intangibles. If biology were determinative, I, as a PROP nontaster, would probably enjoy those sweet, soupy, high-alcohol Australian Shirazes and might not think so kindly of light, acidic red Burgundies. In fact, I generally can't stomach the former and adore the latter. Something happened in my life that dictated these preferences, and it clearly wasn't the genes I was born with.
Viewed from afar, the work being done by Reed, Wysocki, and their colleagues appeared to hold out two conflicting—and, for wine writers at least, equally alarming—possibilities. The research being done into the physiology of taste seemed to carry with it the suggestion that some palates were more naturally gifted than others and that scientists would eventually be able to identify the specific traits that separated the good ones from the not-so-good ones. The insights being gleaned about the psychology of taste appeared to point in a different, but also worrying, direction: namely, that because gustatory preferences were so individualistic and idiosyncratic, no one palate could ever be considered more knowledgeable than another, and any wide-ranging agreement about the merits of a particular wine was more likely the product of groupthink than of true consensus.
Having briefly immersed myself in the emerging science of flavor hedonics, I've come away completely fascinated by the topic—but not especially worried about the implications for my line of work. It is quite possible—in fact, it is more than likely—that there are physiological attributes that are conducive to appraising wines, but we have no idea what they are. We know that the nose is the main conduit through which information about a wine is passed to the brain. Thus, having a "good nose" is helpful. But what anatomical features make for a good nose? We haven't a clue. And as Wysocki pointed out to me, every normally functioning olfactory system has strengths and blind spots. When it comes to judging the bouquet of a Syrah, what are the most desirable strengths and the most debilitating blind spots? We don't have a clue, and because of the aromatic complexity of wine, we'll probably never know.
Moreover, wine connoisseurship involves a lot more than just innate aptitude (if such a thing even exists). It is also a function of motivation, knowledge, experience, memory, and stamina. (You try tasting 60 wines before lunch.) Professionally critiquing a wine involves more than just being able to identify a few aromas. You need to know how the same wine has tasted in previous vintages, how it has tended to evolve, and how it compares to wines that are considered benchmarks in its category—and you need to be able to communicate that information in a way that is meaningful to others.
Some people are better at judging wines than others, but based on what I've learned, the reasons for this are more likely to be found in the brain than in either the nose or the mouth. (And interestingly, researchers have found that for experienced wine tasters, such as sommeliers, more areas of the brain are activated when tasting than is the case for inexperienced tasters.) Moreover, what's striking is how much agreement there is among wine critics. Sure, there is near-universal accord about what attributes a top wine should have—appealing aromatics, ripe fruit, good structure, a sense of harmony in the mouth and a long finish. But given how enormously varied individual palates seem to be, one wouldn't think that there would be much consensus regarding individual wines. However, the critics tend to agree about wines a lot more than they disagree. Taste buds, nasal receptors, and personal tics (my sweetness issue, for example) notwithstanding, wine critics are able to achieve an impressive amount of consensus. Biology is surely a factor when it comes to appraising wines, but it almost certainly isn't destiny.