Word: dna
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...field of biological aging has in recent years focused on the long molecules of DNA contained in human cells called chromosomes. All chromosomes have protective caps at either end called telomeres. Each time a cell replicates itself (as it does before it dies), the telomeres shorten, like plastic tips fraying on the end of shoelaces. Shortened telomeres have been linked to a host of age-related illnesses such as heart disease and certain cancers. (Scientists have yet to study whether telomeres influence a person's appearance.) Last year's Nobel Prize for Medicine was awarded to three American scientists...
...country sits below sea level, so flood control is a major priority. Thus, when canals freeze over, Dutch fans explain that skating on them is cathartic. We have conquered our enemy. Let's celebrate by running our blades all over it! Skating is so ingrained in Dutch DNA that fans talk about one particular race, the "Eleven-City Tour," with the sort of reverence normally shown by global soccer fans for their favorite teams. The Eleven-City Tour is a 125-mile skate over frozen lakes and canals in the northern Dutch province of Friesland. Since all the water...
...hope for its resurrection now lies in its tame descendants, domesticated cattle. Here's how the process is expected to work: Scientists will first scour old aurochs bone and teeth fragments from museums in order to glean enough genetic material to be able to recreate its DNA. Researchers will then compare the DNA to that of modern European cattle to determine which breeds still carry the creature's genes and create a selective-breeding program to reverse thousands of years of evolution. If everything goes as planned, each passing generation will more closely resemble the ancient aurochs. "Everything will...
Back-breeding has an advantage over cloning in that it creates a whole population, rather than just an individual animal. Last year, Spanish scientists used cloning to successfully recreate an ibex that disappeared in 2000, and in Poland another group is trying to clone the aurochs using DNA from bone and teeth samples. But for a species to survive once it's brought back to life, it must have enough genetic variability to reproduce. "A population needs to be adaptive," says Johan van Arendonk, a professor of animal-breeding and genetics at Wageningen University in the Netherlands, adding that...
That's not the only obstacle. Recreating the aurochs from modern cattle won't work if any of its DNA was lost as breeds split apart, experts say. And it will take a lot of time. "The only way we can make recombinations is by having the animals produce a new generation," says van Arendonk. "It's still a very open question if it all can be done...