OK Mutation rates by races - is this a weird article?
BTW I have a cool mutation inherited my mother's side: No wisdom teeth
Dawn of the X-Men? MUTANTS swarm AMONG US, say geneticists
Particularly among weirdo Europeans
By Lewis Page • Get more from this author
Posted in Science, 29th November 2012 15:19 GMT
Humanity has entered a new genetic era, according to a newly published study, with well over half the mutations found having occurred "recently". Potentially troublesome genetic changes are particularly common among those of European heritage compared to those with African forebears, the research shows.
"The recent dramatic increase in human population size, resulting in a deluge of rare functionally important variation, has important implications for understanding and predicting current and future patterns of human disease and evolution," write the authors of the new report, published in hefty boffinry mag Nature.
The study involved gene sequencing carried out on 6,500 Americans of both African and European heritage. Some 73 per cent of the rare (occurring in less than 0.1 per cent of the sample) variations had occurred during the last 5,000 years.
Mutations - genetic variations - sometimes result in improvements (or specialisations) to a human or group of humans, as with the Europeans as they moved out of Africa and became more pale-skinned to cope with the lack of sunlight. X-Men style mutations conferring the ability to shoot frikkin' lazor beams out of one's eyes aren't possible, but things like skin colour, resistance to diseases etc are.
Unfortunately a mutation is more likely to present a problem than an enhancement, and the human race in general is particularly full of them lately because of our massive population explosion over the last 5,000-odd years. Mutations are introduced in each new child (particularly if he or she has an older dad), so populations expanding fast from a small base naturally create more of them.
The relatively small group of mutant Africans who moved north into Europe have subsequently expanded in population particularly enormously, and as a result people of such stock are especially loaded with rare genetic variations.
"One of the most interesting points is that Europeans have more new deleterious (potentially disease-causing) mutations than Africans," says Dr. Suzanne Leal, professor of molecular and human genetics, one of the boffins who participated in the study.
Over the long previous history of humanity, bad mutations (or contra-reproduction ones, anyway) would be scrubbed away by people dying before they had a chance to have kids. But this is a slow process, and it has probably been slowed down even more by modern developments like buildings, farming, medicine etc, even as the rate of mutation has shot up massively.
So humanity is especially riddled with mutants (or mutier-than-normal people: everyone carries at least some mutations compared to their parents), and set to get more so. This could mean health problems - but it could also mean the future appearance of people who are truly unusual in a good (or very strange) way.
Not X-Men, in all likelihood, but perhaps something just as startling.
- Anonymous7 years agoFavorite Answer
Mutation Rates and the Age of the Human Race
Brian Thomas, a science writer for the ICR, has an article up titled "New Genome Projects Data Indicate a Young Human Race." He refers to three recent studies (done for the "1000 Genomes Project") summarized in the journal Science which determined that each human born carries an average of sixty mutations, down from an earlier estimate of one hundred. Thomas raises two separate questions regarding this finding. On the one hand, does the new lower rate provide for enough changes to derive humans and other primates from a common ancestor over the last few dozen million years? On the other, will not the accumulation of harmful mutations over time wipe out the human species, and does this not imply a maximum possible age for the human race?
Thomas used a program called Mendel's Accountant to model a human population over time, assuming sixty mutations per individual. He notes the result:
Assuming a population size of 2,000 individuals, assuming that each mother has six children, and using the rate of 60 mutations per generation in the algorithms, the simulation shows the extinction of the human race after only 350 generations. This also assumes that natural selection would have been effective at removing the least fit from the population every generation.
This account does not mention the percentage of mutations which are beneficial, harmful, or neutral or near-neutral, which the program allows one to select, and whose values, one assumes, would have major import on the outcome of the experiment. I also cannot help but note that Thomas, as a writer for the ICR, is supposed to assume that human populations started out much smaller than 2000 individuals, and have apparently ended up much larger. But that aside, Thomas notes that evolutionists assume that the human species is far, far more than 350 generations old (it is unlikely that H. sapiens is less than 10,000 generations old, and of course we have pre-sapiens ancestors going back long, long before that), whereas creationists assume that the human species is only about 300 generations old (having gone through a really intense bottleneck around 4500 years ago, when our effective population was reduced to Ham, Shem, Japheth, and their three unnamed wives; I wonder if Thomas tried to model that particular feature).
Here is one thing that struck me: the human genome is about the same size as most other mammalian genomes, and there's no obvious reason to suppose that our mutation rate differs much. If we can't survive for a thousand generations, much less ten thousand or ten million, then it's hard to see how rats could. Rats rarely live more than a year in the wild, reach sexual maturity in under two months, and so can have several generations a year. I think that what Brian Thomas' use of "the latest and most accurate research into human genetics" has proved that all rodent species (not to mention all domestic mammals and indeed most supposedly extant mammals) are extinct, which is a somewhat problematic outcome. I cannot help but feel that further research into population genetics, or perhaps just into the assumptions programmed into Mendel's Accountant, are warranted.
- AndreaLv 44 years ago
Who or what determines the definition of "beautiful"? That which is considered beautiful today will not necessarily be thought so tomorrow. Throughout the ages, the yardstick by which society measures beauty has changed and, still, none of society's norms or trends can influence or outweigh personal preference. As for "real dimensions of the human body" ... surely every human body is unique, formed or deformed by so many different factors and influences, that there can be no predetermined dimensions?
- ms mannersLv 77 years ago
If you can't shoot lazer beams from your eyes, I'm not sure why it matters. :o)
My understanding is that most mutations are harmful. And it seem obvious that natural selection would be affected by modern medicine and living conditions artificially extending life.
I'm not sure why the writer is so startled. :o)