Durian is Asia’s “King of Fruits”, a tropical fruit delicacy popular for its pungent smell. Naturally, scientists were curious about durian’s absurd smell. With that, the Singaporean scientists and some international collaborators set on understanding this particular fruit’s entire genetic makeup. And, so far, they succeeded. They deciphered the complete genetic map of the durian truth, the first ever in the world.
Scientists are naturally curious, but even ordinary people would certainly wonder, ‘How come durians smell so bad? Where does the funky smell come from?’ To answer these questions and satisfy their curiosities, a group of scientists in Singapore utilized high-tech sequencing platforms for mapping the genome of Musang King, a particular variety of durian.
Known for its extremely delicate, smooth texture and rich aroma, people regard the Musang King as the “King of the Kings”. The best of the best in the world of durians, scientists begin to analyze the genome of the fruit, which contains about 46, 000 genes. Apparently, durians have genes almost double that of humans, which only has approximately 23, 000.
The complete mapping of durian fruit’s genetic structure allowed scientists to study the evolution of the fruit and of course, how it came to have a pungent smell. The genetic mapping showed how durian evolved 65 million years ago along with its relationship with the cacao plant, its fruit known to produce chocolate.
After comparing the patterns of gene activity of different parts of the Musang King, scientists identify a class of genes possibly associated with the smell. The genes, called methionine gamma lyases(MGLs), regulate production of volatile sulfur compounds (VSCs). VSCs are odor compounds, which in the case of durian fruits appear quite abundant.
The compounds appear consistent with people’s observation that the smell of durian is somewhat sulfury. The scientists deduce that the durian fruits produce high levels of VSC resulting to the pungent smell that attracts animals. This way, animals can pick up and disperse the seeds of the fruit. The technology used for genetically mapping Musang King can also map over 25 other species of durian.
There are plenty of durian species all over the world. Some of them are edible while some are not. Others are also endangered because of the loss of biodiversity. Just like with durian, the platform used for genome mapping of the fruit can open a path for obtaining and protecting valuable information hidden in the genes of all fascinating plants all over the planet.