By Menisha Jitindar Singh
With the average cup of coffee containing anywhere up to 200mg of caffeine, it may come as no surprise that over 120,000 tonnes of caffeine are consumed each year worldwide. Every day approximately 80% of humans consume coffee, tea, soft drinks and energy drinks containing caffeine to keep them alert, have an adrenaline rush and or get a ‘buzz’ but has this become an addiction, or is it simply genetic? A recent study undertaken in America has identified two genes which are affected by the intake of caffeine. Caffeine has the ability to affect the body both mentally and physically, and with the identification of these genetic variants insight into how the caffeine acts inside the body, and how long its effects last could be determined .
Caffeine is a stimulant that affects the central nervous system in humans. To nerve cells caffeine looks like adenosine. Adenosine is created in the brain and binds to adenosine receptors. This binding is the cause of drowsiness because the binding slows down nerve cell activity. Consequently, when caffeine molecules bind to the adenosine receptors the nerve cells sped up instead of slowing down .
Upon completing a study about the caffeine intake by 47,341 individuals in America the role some of the human’s genes play in the metabolism of caffeine was determined. With this being the first Genome-Wide Association Study of “habitual caffeine consumption” it was discovered that the genes CYP1A2 and AHR were possible candidates for genes that affect caffeine intake . Observations suggested that CYP1A2 was involved with the metabolism of caffeine and AHR was involved in the regulation of CYP1A2. Individuals who possessed the highest-consumption genotype for either of genes consumed approximately forty milligrams more caffeine than those who possessed the lowest-consumption genotype .
In Conclusion, with the completion of first Genome-Wide Association Study on habitual caffeine comsumption there is potential to find out more about the possible link between caffeine intake and genes. At present, it has been determined that there are two genes that play a role in the metabolism of caffeine within the body. These two genes, depending on consumption genotype also help determine the general amount of caffeine ingested. This shows that the way, and amount, of caffeine that we drink may not be random, but may be imprinted in your genes and based on our metabolism speed.
View original article at http://www.sciencedaily.com/releases/2011/04/110406091731.htm
View original journal article at http://www.plosgenetics.org/article/info%3Adoi%2F10.1371%2Fjournal.pgen.1002033
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