基因变异 z-bo 2020-10-16 284

　　It is all fish. Some people think it is fresh, while others think it is a lot. Why? Relevant studies on the new genome have shown that people’s olfactory receptor gene mutations can affect people’s sensitivity to fishy odors.

　　In order to explore the genetic basis of smell, researchers from Iceland's DeCode Genetics conducted a genome-wide association study (GWAS) on more than 9,000 individuals. These people took part in the odor test at the same time and sniffed out six different odor samples. Researchers reported in the journal "Contemporary Biology" this week that mutations in the TAAR5 gene affect the perception of odors in fish, while certain mutations affect the perception of other odors. Rosa Gisladottir of DeCode Genetics, the lead author of this article, said: Do we like these foods?

　　The sense of smell is very important to humans. If your nose is blocked, the food will become tasteless and tasteless. There are more than 850 olfactory receptor genes in the human genome, but about half are considered non-functional. However, the sequence diversity of the remaining olfactory receptor genes is increasing, which indicates that the personalized combination of mutations can affect people's odor and odor intensity.

　　In this survey, Gisladottir and his colleagues investigated 9,122 Icelanders in GWAS. These participants completed a series of olfactory tasks simultaneously. You need to use a sniffing stick to sniff six kinds of licorice, cinnamon, lemon, fish, mint and banana to convey the smell and evaluate its strength and comfort.

　　Generally, the smell of fish is generally considered the most unpleasant, but the mint smell is the easiest to recognize. And, as one might expect, people’s assessment of odor intensity decreases with age. The researchers found mutations related to smell at three loci. The missense mutation in TAAR5 is related to whether people feel fishy, and the three chain mutations OR6C70 and OR6C68 are related to the smell of licorice. In addition, mutations on chromosome 11 can affect whether people smell cinnamon. They then verified the results with 2,204 other Icelanders.

　　They found that the missense mutation p.Ser95Pro of TAAR5 gene reduced the intensity of fishy smell. The mutant participants were unable to accurately convey the smell of the fish while improving their odor comfort. They usually do not use smelly items (such as smelly shoes) to describe the smell, but often use neutral or interesting words (such as ketchup, caramel, and roses).

　　Computer analysis predicted that mutations in p.Ser95Pro would destroy protein function. The researchers pointed out that the location of this variant affects nearby highly conserved amino acids that are involved in the interaction of TAAR1 and TAAR5 ligands.

　　According to the Genome Clustering database, researchers found that the frequency of p.Ser95Pro mutations varies from population to population, with 2.2% of Icelanders, 1.7% of Swedes, 0.8% of Southern Europeans and only 0.2% of Africans. I pointed it out. The frequency of alleles that affect the odor perception of cinnamon and licorice also varies from population to population, indicating that human odor perception may still be naturally selected.