
01 Oct 2014 Glorious coffee’s DNA tells many fascinating tales
With more than 2.25 billion cups consumed every day, coffee is one of the most important crops on Earth. The DNA of the robusta plant has now been deciphered, and the unravelling of its mysteries holds many an interesting tale…..
CHARLES Darwin did a fine job of showing why his theory of evolution explained the living world better than any creationist ideas could, and evidence has piled up ever since, but a swatch of the American public remain unconvinced. Therefore, it’s always good to come across new scenarios to show how evolution works and debunk some of the misconceptions spread by proponents of “intelligent design” and other versions of creationist mythology.
On the surface, coffee might seem like a good candidate for a plant that was not only designed by an intelligent god but by a god that was feeling rather benevolent toward us humans. After all, this plant produces a bean – technically a seed – that smells heavenly, tastes satisfying, makes us feel good, and isn’t even bad for us.
There used to be some confusion but now, scientists have had the chance to observe lots of coffee drinkers for long periods of time and not only do they find no connection with heart disease or cancer, but they even see hints that those who indulge regularly may be less likely to get liver cancer or type 2 diabetes.
Rob van Dam, a professor of nutrition associated with the Harvard School of Public Health, said some of the confusion in the past came from the fact that coffee is so pleasant to drink that it was favoured by indulgent type people – those who slept too little, drank a lot of booze and smoked a lot of cigarettes. By association it seemed that coffee ought to be bad. And the fact that it was mixed up with various unhealthful habits made it hard for the experts to detangle things and tell us whether coffee was good or bad for health.
Some of the best data we have on coffee now comes from the Nurse’s Health Study and the Health Professionals Follow-up Study, said van Dam. When looking over lots of people for decades, coffee looks to be, if anything, a healthy choice for most people. But there’s still more to learn, he said, since coffee packs a huge number of different compounds, caffeine being just the most popular and well known.
All this raises the question of how evolution alone could produce something so complex and so wonderful. Not that there was any doubt, but scientists now have the story pretty well fleshed out after deciphering the DNA of the coffee plant in a project known as the Coffee Genome Project. The results were published earlier in September in the journal Science.
Victor Albert, a biologist at the University at Buffalo, who was part of the effort, said that there will be important applications for coffee growers. How could such a study fail to be useful considering there are 2.5 billion cups of the stuff consumed every day?
There are a bunch of species of coffee, only a few of which make caffeine, said Albert. The genome analysis used robusta coffee, which makes up about a third of coffee consumed. The other popular species, arabica, is a hybrid of robusta and another species.
For Albert, the work is exciting because it’s telling us something about evolution…..