Coffee is the watchdog par excellence, it helps tired morning muffles in the day and keeps fit, if it takes time in the evening a bit longer. But also the complex, rich aroma of the fragrant hot drink entices us to enjoy. No wonder coffee is one of the most popular drinks worldwide - coffee consumption is only surpassed by water and tea. After the coffee was vilified by previous generations as unhealthy, has become more and more in recent years that the plant product coffee even health benefits. Thus, studies suggest that coffee protects the blood vessels and has a positive effect on the fat and sugar metabolism. Even our memory should strengthen the regular enjoyment of coffee and preserve our genetic material from damage. In addition to caffeine, it is most likely responsible for the polyphenols and other phytochemicals contained in the coffee bean. Researchers mostly observed all of these healthy effects in those who have been eating regularly and often more coffee per day for years.
But what decides whether we are coffee drinkers or can easily get through the morning with the "Wachmacher" cup? For a long time, scientists have suspected that playing more here than just the individual liking for taste or the habit. "The earliest studies on a genetic basis of coffee consumption date back to the 1960s, " explain Nicola Pirastu of the University of Edinburgh and his colleagues. They investigated whether identical twins are more similar in coffee drinking behavior than dizygotic twins or normal siblings - with weak positive results. In recent years, researchers have identified several genes whose variants could influence how much coffee a person drinks. "But despite these successes, the inheritance of the desire for coffee still remains largely unexplained, " Pirastu and his colleagues state.
Found on chromosome six
To bring more light into our "coffee genius", the researchers have again sought in the genome. They asked about the drinking behavior of a good 1200 people in Italy and about 1700 Dutch. At the same time they took all DNA samples, sequenced the genetic material and performed an association analysis. They searched specifically for gene variants that occur frequently in frequent or low drinkers. The result: Twelve deviations in individual DNA bases showed a correlation with coffee consumption, as the scientists report. These variants concentrated in a specific region of chromosome 6: in the PDSS2 gene, a gene that contains the blueprint for part of coenzyme Q10. The Q10 is known to most of us as an adjunct to skin creams, but in the liver, this coenzyme influences how effectively caffeine is broken down. Pirastu and his colleagues have now found that gene variants that lower the activity of the PDSS2 gene, especially in people with particularly high coffee consumption can be found.
"With this we have discovered a new connection between the coffee consumption and the PDSS2 gene, " say the researchers. They suspect that the relationship manifests itself as follows: In humans, where this gene is very active, the caffeine degradation is down regulated - the effect of a cup of coffee therefore lasts long. However, those who carry PDSS2-inhibiting gene variants, the caffeine breaks down faster and therefore tends to earlier drink the next cup of coffee. He is one of the drinkers. However, the connections are not as simple as explained here, of course, as the researchers emphasize. Because the PDSS2 gene is only one of several known genes that could influence the coffee consumption of a human. In addition, our environment, habits and circumstances also play a crucial role in whether we drink a lot of coffee or not in the course of a day. display
- Nicola Pirastu (The University of Edinburgh, UK) et al., Scientific Reports, doi: 10.1038 / srep31590