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Durian(榴莲) is probably the smelliest fruit in the world, letting out an unusual unpleasant smell which would make anyone bring up. However, nobody was aware of what gave this fruit its unique smell, so a team of researchers from Singapore decided to take a look at its genome (基因组) and find out,
Durian is well-known throughout Southeast Asia as the king of fruits, mostly because of its awful appearance and smell. However, the origin of this unpleasant smell was unknown, so researchers decided to map the genome of the fruit, and find the gene that controlled it. A group of genes, volatile sulfur compounds (含硫化合物), became very active in the fruit, and they were found responsible for resulting in the unpleasant smell.
The fruit confuses everyone with a sulfuric smell, like rotten onions and ingredients. The smell lasts long, mostly because the fruit contains more volatile sulfur compounds. Other species usually benefit from two gene copies at most, but durian has four, leading to the striking smell.
However, this smell might be an advantage for durian in the wild. Although we find it unpleasant, many animals might be attracted by it. If they eat the fruit, then they can easily spread its seeds everywhere, thus contributing to the distribution of the species.
The mapping of the durian genome also showed some other information on the species. First of all, the fruit has an impressive number of genes, namely 46,000. Also, with the help of these genes, they saw how it evolved, and discovered it was related to the cacao tree. All the other discoveries have been published in the journal Nature Genetics.
Despite the striking smell, many people actually enjoy eating the fruit. However, not all durian species are edible, and some of them may even cause damage to our health, Even so, the fruit is often imported, significantly contributing to the economy.
