Stupid question but- can one's DNA change over one's lifetime (i.e. with mutations, etc.)?
546065
Not a stupid question at all. Mutation (as mentioned above) does occur, though of course it will only affect individual cells and their descendents, not all cells in the individual. There is also a process that is being increasingly studied called genomic imprinting or epigenetic inheritance. These are not DNA sequence changes, like you asked about, but seem to be related to your question. The wikipedia article is a decent introduction but there are other summaries available.
389612
Everything about a life form is decided by DNA from the colour of it's fur or skin to it's size. This is what our parents pass on to us. However, if this is not copied properly when it is passed on to an egg or sperm cell, which becomes a baby, then the baby may have a different characteristic from the rest of its species. This is called a mutation. If this mutation gives the animal an advantage over other animals in it's species- for example if it makes a moth brown instead of white so it can blend in on trees more, and is less likely to be eaten by predators, then that animal is more likely to survive. If it then mates and passes on it's mutated DNA to more offspring then they are more likely to survive so slowly the white moths would be eaten where the brown would not, and the species has 'evolved' to be brown. Every animal you can think of has been formed by tiny mutations over millions of years. We owe evolution quite a lot!
1156545
In general changes to the DNA of a species poses a risk of unexpected results.  Nature is generally in more or less of an equilibrium.  When sudden changes occur that balance can be upset.  Like when new predators are introduced into an area and their prey is wiped out.  Or when a plant is introduced to a new area and spreads uncontrollably.\n\nCreating "new" plants can have the same kind of impact as moving plants around from one part of the world to another.\n\nAdditionally there is some concern that taking DNA from one plant and embedding it in another plant's DNA (e.g. to improve resistance to insects, drought, etc.) could have adverse effects (e.g. producing allergic reactions where none had existed).\n\nThere's no right answer.  As with any technology we have to weigh the total impact (on humans, the environment, etc.).
182301
Alleles. Mutations are just general changes in the DNA, they do not necessarily have to be in a gene, therefore, not all mutations cause the creation of new alleles (ie if a mutation occurred in an area that did not code for anything)
613
Interestingly phrased.\n\nYes, I would say that DNA is the map from where we are coming from. Researchers are using DNA and the relative similarities of certain sequences to deduce just how long ago we diverged from previous forms.\n\nWhat I mean by that: evolutionarily speaking, everything living on earth today can be traced back to a common ancestor (LUCA - Last Universal Common Ancestor). The bigger the difference in the sequences of two species DNA, the longer ago we diverged from that common ancestor and the less related the two organims are to one another -- meaning there are more intermediate organisms between their current status and the ancient ancestor shard by the two.\n\nWe can use DNA not just to illucidate species broad histories, but individual histories too. We have a very unique piece of DNA in our cells. It is contained in our mitochandria. Mitochandria are little energy plants in our cells. The DNA in mitochandria, unlike the rest of our DNA, as we know it, is passed down only from our mothers. So, based on that, this DNA is less diverse. Any differences in this DNA has to come from mutations. Because the mutation rate is relatively slow, there are key "markers" that have appeared from time to time in specific subgroups of humans over time. So the markers you contain in your mitochandrial DNA are indicative of where which subgroup you are a decenent of. These subrgroups can be indicative of races, but as the more information we collect on the various markers from around the world, we'll be able to determine specific regions from which your ancestors lived and migrated to throughout history.\n\nAs far as a map to where we are going, I would say that DNA is that too, but that is less able to be predicted. Our DNA will definitely determine how our species continues to evolve. Let me give you an example. Let's say that this bird flu pandemic that the media has been stressing over the past 6 months actually does happen sometime in the future. An individuals ability to survive such a pandemic will be directly linked to their specific genetic sequence. Some will be innately immune to infection and thus will probably survive the pandemic. Others will not be so lucky. If the speculation is true and hundreds of millions of people do die, their genetic makeup will be eliminated -- thus those genes that make up those people will be removed from the general gene pool. The remainder of people will determine the fate of humankind. If another pandemic was to follow years down the road and the genes that were left over were succeptble to that infection, it could mean the end of the human race. More than likely though, there will always be some subset of the population whose genes allow for survival. From there, the future of humans depends on how overall fit those genes are.
103912
I disagree with Cobra.  Cloning an old human being will not result in advanced aging in the clone.  Remember dolly, the cloned sheep?  At first, scientists thought that she would age much faster than a regular sheep.  This, however, was not the case.\n\nAnd, since the clipping of telomeres (that change in your genes that Cobra was talking about) is the only change that occurs in the genes during the life of a human (barring radioactive exposure), cloning a 100-year-old human would have the same result as cloning the same human when he or she is an infant.  No difference, no additional mutation.\n\nFor info about dolly's aging, see the below article under "Controversy."
950574
It's a key element in evolution, and comes about through modifications of an organism's DNA via radiation, chemical poisoning, or simple mischance in cell replication.  The daugther organism can inherit the modified DNA, and it may - or may not - give some advantage toward survival and subsequent reproduction.
656214
I would like to see a computer program that simulates evolution. It can mutate anything it wants a million times a second. Bring it on baby, or shut up until you do. (not speaking to you Tom but to evolutionists who can't reproduce evolution even in a computer without cheating).
1172039
We are constantly evolving. If you look at statistics over the last hundred years, people are getting taller. (Go into an old, old home - the stairs will be smaller - people were smaller.)\n\nEvery time that DNA replicates, there is a possibility for an error. These can be positive or negative, but it the error is transmitted to the next generation, it will make changes in person. These changes are EVOLUTION. \n\nUnfortunately, the survival of the fittest isn't accurate anymore, as people with defects are now living long enough to reproduce and making faulty copies of their DNA. \n\nWe will continue to change, slowly, but evolution is happening all around us, and in us, everyday.
96132
There have been hundreds of thousands of such experiments done. Moreover you can easily do them yourself using some nutriemt agar and an incubator with a few hundred dollars to pay someone to do the genetic workup.\n\ntalk.origins is your one stop shop for these types of quetsions. The site is highly reputable, well refernces, cites peer reveiewed science journals and most importantly lists literally hundreds of experimenst that show exactly what you describe.\n\nI've attached a couple link to pages that list a dozenor so such mutation studies, but the site has many hundreds of others.
384649
mutation- it is the heritable change in the genetic material ie DNA of an organism.it can involve changes in gametes (germline mutations) and changes in body cells (somatic mutations). \n\ncheck out this site for info:
644978
a mutation can change the DNA but not the amino acid sequence because in order to get a protein there are several options for DNA. (for example) you can UAG as a protein and you can get that by ATG, CGC, AUC and more.  So that gives you a chance to get the same amino acid with a change in the DNA.
1042798
The current understanding of the biology of aging and disease is still quite limited, to the point that we probably won't see any major breakthroughs in the next century. There have been some studies in model organisms (such as the nematode and the fruit fly) that suggest that there are genes that regulate aging. However, this is not well understood in these organisms, and very poorly understood in humans. There are human cell lines (cells that grow in growth medium) that are "immortalized," that is, they continue dividing apparently forever, but these are a far cry from an organism put together like you or I. These cells often come from cancerous tumors and have extremely disrupted genotypes, such that basically all they can do is grow and divide. \n\nNot only do we understand little about the aging process itself, but any hopes of human genetic engineering depend on the ability to change a person's genetic complement. This, of course, is remarkably difficult in adults, who have countless cells that would have to be changed. Some "gene therapy" techniques have been tried in humans, including viral vector-based gene delivery systems. These show some promise, but there haven't been any major breakthroughs. An alternative is to try to engineer an organism from the very beginning; that is, to manipulate a zygote. However, this is widely considered to be unethical, at least in the case of humans.\n\nMy opinion is that through genetic technology, we will make better and more effective cures and preventative therapies, which will have the potential of increasing the length and quality of our life. Overcoming death is a completely different story (and a very interesting question for philosophy and religion!).
312318
NatBoCheck: Well for starters even creationists believe in microevolution, but then you probably don't know what that is.\n\nGive me a few mins...\n\n"The process of evolution can be summarized in three sentences: Genes mutate. [gene: a hereditary unit] Individuals are selected. Populations evolve."\n\n"The mechanisms of evolution are mutation, natural selection, genetic drift, recombination and gene flow."\n\nMutation\n\nThe cellular machinery that copies DNA sometimes makes mistakes. These mistakes alter the sequence of a gene. This is called a mutation. There are many kinds of mutations. A point mutation is a mutation in which one "letter" of the genetic code is changed to another. Lengths of DNA can also be deleted or inserted in a gene; these are also mutations. Finally, genes or parts of genes can become inverted or duplicated. Typical rates of mutation are between 10-10 and 10-12 mutations per base pair of DNA per generation. \n\nNatural Selection\n\nSome types of organisms within a population leave more offspring than others. Over time, the frequency of the more prolific type will increase. The difference in reproductive capability is called natural selection. Natural selection is the only mechanism of adaptive evolution; it is defined as differential reproductive success of pre- existing classes of genetic variants in the gene pool.\n\nThe most common action of natural selection is to remove unfit variants as they arise via mutation. [natural selection: differential reproductive success of genotypes] In other words, natural selection usually prevents new alleles from increasing in frequency. This led a famous evolutionist, George Williams, to say "Evolution proceeds in spite of natural selection."\n\nNatural selection can maintain or deplete genetic variation depending on how it acts.\n\nGenetic Drift\n\nAllele frequencies can change due to chance alone. This is called genetic drift. Drift is a binomial sampling error of the gene pool. What this means is, the alleles that form the next generation's gene pool are a sample of the alleles from the current generation. When sampled from a population, the frequency of alleles differs slightly due to chance alone.\n\nAlleles can increase or decrease in frequency due to drift. The average expected change in allele frequency is zero, since increasing or decreasing in frequency is equally probable. A small percentage of alleles may continually change frequency in a single direction for several generations just as flipping a fair coin may, on occasion, result in a string of heads or tails. A very few new mutant alleles can drift to fixation in this manner.\n\nRecombination\n\nEach chromosome in our sperm or egg cells is a mixture of genes from our mother and our father. Recombination can be thought of as gene shuffling. Most organisms have linear chromosomes and their genes lie at specific location (loci) along them. Bacteria have circular chromosomes. In most sexually reproducing organisms, there are two of each chromosome type in every cell. For instance in humans, every chromosome is paired, one inherited from the mother, the other inherited from the father. When an organism produces gametes, the gametes end up with only one of each chromosome per cell. Haploid gametes are produced from diploid cells by a process called meiosis.\n\nIn meiosis, homologous chromosomes line up. The DNA of the chromosome is broken on both chromosomes in several places and rejoined with the other strand. Later, the two homologous chromosomes are split into two separate cells that divide and become gametes. But, because of recombination, both of the chromosomes are a mix of alleles from the mother and father.\n\nRecombination creates new combinations of alleles. Alleles that arose at different times and different places can be brought together. Recombination can occur not only between genes, but within genes as well. Recombination within a gene can fo
482717
No. \n\nMany risks for humans can not be noticed in a short time. Studies lasting 5-10 years are more than funny when we think that natural genetic diversity was formed during millions of years and humans developed in a given environment. Even compounds, which have nothing to do with so deep change as genetics, prove having impact only starting from third generation. \n\nThe world is a complex thing. It is impossible that one change would not cause another change. HUmans are too limited to forecast risks; besides far not always most clever heads take political decisions. Present knowledge permit to make a world without hunger not employing trasgenetic plants, but simply other intetests guide. \n\n3. Changes will be irreversible. And humans can not recreate newly normal lost environment. Not only genetics. Even simpliest mead, in fact. So spead of transgenetic crops is very irresponsible thing.\n\nInteresting, is it true thing in this article:\nhttp://www.wintersteel.com/Mutation.html
575617
You don't have to be of any certin age. Your DNA wont change.
113213
Ahem. People, he's asking about the RATE of change. Not whether changes occur or whether evolution occurs. He clearly already knows that.\n\n__________________________________\n\nWell done. You’ve asked one of the most controversial questions in current evolutionary biology.  Much debate rages about this subject right now. \n\nWhat you are describing is commonly referred to as the evolution of evolvability. As you point out, if a population doesn’t have sufficient variation then environmental change could lead to extinction. But at the same time if the population is too variable the outliers will simply perish in current conditions. For example if elephants contained the inherent variability to produce young twice as big or the size of a rabbit those individuals would die.\n\nThe belief was for 100 years or so that the selective pressure of current environment would maintain a fairly tight rein on variability, that mutation rates were approximately constant and that survival in times of change was simply a case of pot luck. But then people started to look at the fossil record and the real world and it seemed like that wasn’t plausible. Novelties seemed to appear almost overnight, and they appeared almost any time they were needed. \n\nSo then came the concept of punctuated equilibrium. The idea that  a population would sit still for long periods, then as conditions changed they would suddenly leap forwards into a radically different form. That was all well and good, but it was basically just a restatement of the observations, not really an explanatory theory.\n\nIn the past 15 years ago there has been a lot of debate about the idea that organisms have evolved to evolve. That they have evolved in such a way that they are physically stable in times of environmental stasis, but when the environment becomes stressful change they can either mutate more, or reshuffle genes or express pattern of dormant genes to produce stable phenotypic novelties at rates that far exceed background rates.\n\n\nThe theory certainly makes sense. It’s hard to argue that such a trait wouldn’t; be a survival advantage. Unfortunately the evidence is ambiguous. And at the moment there are umpteen dozen theoretical mechanisms to explain how it could occur, and they are impossible to separate out. There is some work which has shown that many species can open up dormant genetic material for expression and re-assortment in response to stress (see first link below). And some experimental evidence suggests mutation rates increase in response to environmental change. Some say that prions are the key. Other favour inherent genetic instability in those individuals that survive initial changes, meaning that the decedent population is inherently prone to genetic varaiation until the environment stabilises and kills of the outliers again. Other propose that assortment of populations within the same or closely related species could explain it. But at this point we can’t even prove that genetic variation does change under stress. But at this point we just don’t know. \n\nYou ask a damn good question but the concept is hard to study and harder to establish with any certainty.\n\n_______\n>>>>Being able to actually understand how, and under what\n>>>> circumstances mutations happen strikes me as extremely\n>>>> important.\n\nWe've actually got a pretty good handle on how and when mutations occur. This is more of a question of when they are expressed or encouraged. Organisms have the ability repair genetic damage thorugh several mechanisms. They also have the ability shield the nucleus fom many mutagens. The issue is whether they may be able to damp down those processes to encourage more mutations.\n\n>>>> I can definitely see that species that do not have the \n>>>>capability to mutate in response to external forces\n>>>> would be selected against.\n\nYes, it's a rather hard