I have heard it said by creationists that there are no modern benificial mutations. They state that all mutations are harmful, leading to genetic diseases and such. This, to them, seems to point that evolution is flawed.
However, I have also heard that in very rare cases, HIV does not turn into full blown AIDS. These people become carriers, and are not harmed by the virus. Is this not a benificial mutation?
Comming from the theory that HIV is an old virus that effects monkeys, and has monkeys have evolved to adapt to it. Once it was transfered to humans (yuck), our immune system was ripe for it, and not adapted to fight it. The immune cases seem to suggest that some small percentage of humans have adapted to this dastardly virus.
(if this is the case, why not study the genes of the immune cases, and try to figure out what gene sequence causes this “immunity”. This could very well lead up to a cure, could it not?)
Is this a case of evolution in the works? A benifical mutation, that would allow humans to carry on, killing off those not adapted?
This seems more of a GQ than a great debate. I want this to be debated though, and would really like to see if, perhaps, there are other cases such as this. Immunity to the foot in mouth disease? Was there ever any peoples that were immune to smallpox? What other kind of benificial mutations are obvious in modern history?
The germs that are evolving resistance to modern drugs are certainly mutating in ways beneficial to them (no so beneficial to us).
Lactose tolerance.
We have a type of bacteria that has “learned” to digest nylon through a single transcription error in a protein.
That’s a pretty beneficial mutation for a bacteria.
What idiot said that?
Bacteria have beneficial (for them at least) mutations all the time. They acquire resistance to all kinds of antibiotics, insects acquire resistance to pesticides, and plants acquire resistance to insects.
Remember the human genome is HUGE, it’s not the same as those of plants and insects, an anomaly may not show up phenotypically for generations. In addition, it has a lot of redundancies. Unlike the genome of a bacteria, a single point mutation, in all likelihood, will have no phenotypic effect, because another gene will take over its job.
However, that said, if a Creationist believes that mutations occur, than aren’t they losing the argument right there?
In a primordial world, those with the mutation that cause diseases and such would have died. Doesn’t that make their argument invalid in some way shape or form? I mean, I don’t know of a single person who has claimed that Darwinian evolution occurs in a couple of hundred years.
I would think that the resistance to HIV is pretty new, and has occured within the last 100 years. To me, it is hard evidence of evolution at work.
Mutations for HIV resistance (which can occur in the CC or CRC chemokine receptors) may not necessarily be new – when the mutation occurred is not calculable. What is true is that now it is being selected for. Evolution is two part – mutation with selection. What we are seeing is selection in the human population. If this selection is strong (let’s say in Africa where you have 1/3 of the adult population HIV+) and prolonged (there is no “cure” or cheap treatment for AIDS any time soon) what you will see is evolution in the human population.
Another aspect to these mutations may be that they presumably decrease fitness in a non-HIV setting to a certain extent. The increase in fitness given by AIDS resistance needs to of course be greater than the decrease by the mutation. The way the numbers would change in a population is a complex population genetics question which I don’t currently possess the skills to do. If you are really interested, I am just downstairs from those who do have the skills, however.
I meant CXC not CRC chemokine receptors (for those of you out there on literature searches).
My understanding of the Creationist argument is that all observed genetic mutations are harmful, yet Evolution rests upon the cumilative effects of many, co-inciding, beneficial mutations in order to evolve from one species to another.
Gp
While two Sickle-cell Anemia genes cause illness, a single gene (ie heterozygous SCA) protects against malaria.
some info:
http://www.kie.berkeley.edu/ned/data/E01-980311-003/E01-980311-003.html
if you search “sickle cell malaria” there’s loads of articles.
I was born with 3 wisdom teeth…that count?
There is also a group of people in Italy that have a genetic resistance to heart disease. They do not get the cholesterol build up on there arteries. Sounds beneficial to me.
Actually, this isn’t really the case. The human immune system is very well adapted to fight off the invaders. The problem is, the virii are better adapted at mutating in an effort to foil our immune systems. When first infected, most of the virii are dealt with; however, because of the rapid mutation rate of the virus (caused, as I understand it, by a somewhat lazy transcripting mechanism and/or limited error-checking), it doesn’t take long before mutations arise which can evade or otherwise circumvent the immune system. These virii then perpetuate and spread the disease. A clear case of natural selection at work.
Of course, “harmful” and “beneficial” are not determined by our anthrocentric prejudices, but it sounds good to me. HIV resistance (reference the above URL) is also something of which I’m in favor.