The next time you make a face at the cilantro (coriander in certain parts of the world) on your plate, you can blame your genes. A genetic component for the intense dislike of cilantro has been found.
Before you get outraged by the thought of studies performed on culinary preferences, responses to cilantro has been thought of as interesting for quite a while. There are polarizing reactions to it, with some people comparing its taste to soap. On the other hand, it continues to be used generously in South Asian and Latin American cuisines. This even prompted the New York Times to publish an article called ‘Cilantro Haters, It’s Not Your Fault’.
The distinct flavor of cilantro is because it contains a class of molecules called aldehydes. It was thus hypothesized that differences in proteins that can detect these molecules—called receptors—could be responsible for the strong variation in response to the herb. Now, researchers at the sequencing company 23andMe have used genome sequences of 14000 Europeans to hunt out a genetic cause.
This research was part of a larger group of projects under 23andMe, which could be called crowdsourcing. In this process, the company sequences people’s genomes and provides genetic analysis. Clients willing to participate in 23andMe’s research are then asked to fill up a questionnaire about various traits that might be genetic, for instance, whether they think cilantro has a ‘soapy’ taste (another example could be eye color). The company then uses this data for their analysis. In this experiment, they found that one varying position in the genome—called a single nucleotide polymorphism (SNP)—was found to be associated with the way people think cilantro tastes. To put it another way, people who detest cilantro were much more likely to have one version of this SNP as opposed to people who like it, who are more likely to have another version.
Having found this SNP, they realized that it lies within a cluster of 8 olfactory receptor genes, genes involved in the perception of smells. This could thus be a strong candidate gene responsible for the divisive response to cilantro.
However, this SNP only explains a very low percentage of the variance in the trait. What does this mean? Ideally, we would expect to be able to predict a person’s response to cilantro based on the SNP she has. However, that is not the case, only 1.5% of the variance in the trait can be explained. This could be because there are multiple genes that act together in determining cilantro response (and they have only managed to capture one of them), or that only a small amount of cilantro response is actually genetic. Thus, in the latter case, even a significant SNP cannot significantly affect cilantro detection. This study was only performed on a European population, studies capturing a greater diversity could yield further answers.
You can read about this research here.