Pattedyr (incl. mennesker) er katalyseret af vira?:
February 14, 2012, blogs.discovermagazine.com: Mammals Made By Viruses: Citat: "... In 2000, a team of Boston scientists discovered a peculiar gene in the human genome. It encoded a protein made only by cells in the placenta. They called it syncytin. ... What made syncytin peculiar was that it was not a human gene. It bore all the hallmarks of a gene from a virus. ... Viruses have insinuated themselves into the genome of our ancestors for hundreds of millions of years. They typically have gotten there by infecting eggs or sperm, inserting their own DNA into ours. There are 100,000 known fragments of viruses in the human genome, making up over 8% of our DNA. Most of this virus DNA has been hit by so many mutations that it’s nothing but baggage our species carries along from one generation to the next. Yet there are some viral genes that still make proteins in our bodies. Syncytin appeared to be a hugely important one to our own biology. Originally, syncytin allowed viruses to fuse host cells together so they could spread from one cell to another. Now the protein allowed babies to fuse to their mothers. ... Later, the French virologist Thierry Heidmann and his colleagues discovered a second version of syncytin in humans and other primates, and dubbed them syncytin 1 and syncytin 2. Both virus proteins seemed to be important to our well-being. In pre-eclampsia, which gives pregnant women dangerously high blood pressure, levels of both syncytin 1 and syncytin 2 drop dramatically. Syncytin 2 also performs another viral trick to help its human master: it helps tamp down the mother’s immune system so she doesn’t attack her baby as a hunk of foreign tissue. ... They shut down the syncytin A gene in mouse embryos and discovered they died after about 11 days because they couldn’t form their syncytiotrophoblast. So clearly this virus [protein?] mattered enormously to its permanent host. ... The big picture that’s now emerging is quite amazing. Viruses have rained down on mammals, and on at least six occasions, they’ve gotten snagged in their hosts and started carrying out the same function: building placentas. ..."
Så havde man hovedløst "renset" menneskets genom for ikke-humane gener, ville vi have fjernet muligheden for at få børn - og dermed udslettet os selv.
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Der er indicer på at der findes gode vira:
19 November 2014, newscientist.com: ‘Good viruses’ defend gut when bacteria are wiped out: Citat: "... One group of these mice, and another that hadn’t received the virus were then given antibiotics, which wiped out much of their gut flora. Both groups then ingested a potentially fatal gut-irritating chemical. Those with the virus were much more likely to survive than those that hadn’t received it. ... So could the results in mice apply to people? Possibly, says Cadwell. Viruses are routinely detected in young children who don’t show any symptoms, and also in people recovering from acute bacterial infections of the gut. This suggests that the presence of some viruses might be beneficial during development or periods of recovery when the immune system and gut bacteria are at their most vulnerable, he says. ..."
May 13, 2015, natureworldnews.com: Viruses: They're Not All Bad, Says Expert: Citat: "... Then there's the herpes virus. You read that right, herpes - the unmentionable sickness which boasts strains that can cause painful cold sores or (heaven forbid) an incredibly persistent and harmful sexually-transmitted disease (STD). According to a number of past studies cited in Roossinck's work, a latent herpes virus (one that is dormant) may naturally arm the cells they infect with the ammunition to kill both mammalian tumor cells, and cells that are infected with pathogenic viruses. ... Recent investigations determined that to live there, plants form a complex symbiotic relationship between fungi and the viruses that infect them. Field work and lab-side studies determined that this three-way 'agreement' could likely allow most plants to hash out an at-least struggling existance in these normally fatal temperatures. Even tomato plants were found to withstand up to 140 degrees (60 C) as long as all three members of the relationship were present. ..."
May 16, 2007, livescience.com: The Good Thing About Herpes: Citat: "... The herpes family of viruses can have a surprising upside--it can protect against the bubonic plague and other bacterial contagions, at least in mice. ... "There may be symbiotic advantages to chronic infections with these viruses." These new results do not mean people should go out and get infected with herpes, Virgin stressed. They probably already are. Nearly all humans become infected with multiple herpes virus family members during childhood. ... Still, while people might benefit from symbiotic relationships with the herpes family of viruses, they can also have serious consequences, such as deafness, blindness, encephalitis and cancer. ..."
31 Aug 2012, telegraph.co.uk: A virus that kills cancer: the cure that's waiting in the cold: Citat: "... It sounds too kindly of the gods to be true: a virus that eats cancer. ... In Prof Essand's laboratory studies his virus surges through the bloodstreams of test animals, rupturing cancerous cells with Viking rapacity. ... The Uppsala virus isn't unique. Since the 1880s [1980s?], doctors have known that viral infections can cause dramatic reductions in tumours. In 1890 [1990?] an Italian clinician discovered that prostitutes with cervical cancer went into remission when they were vaccinated against rabies, and for several years he wandered the Tuscan countryside injecting women with dog saliva. [] In another, 20th-century, case, a 14-year-old boy with lymphatic leukaemia caught chickenpox: within a few days his grotesquely enlarged liver and spleen had returned to ordinary size; his explosive white blood cell count had shrunk nearly 50-fold, back to normal. ... There are reasons to be cautious. A recent investigation by Amgen found that 47 of 53 papers (on all medical subjects, not just viruses) by academics in top peer-reviewed science journals contained results that couldn't be reproduced, even though company scientists repeated the experiments up to 50 times. ..."
