But it’s “unnatural”…
I’m not impressed with this argument either. Preventing ovulation with oral contraceptives was not “natural” either; neither was using microwaves to heat food by causing friction between the molecules instead of radiant heating…the list is endless.
‘Unnatural’ isn’t used as a value judgment…
My point is that attempts to clone an organism with adult, specialized cells “goes against” what the genetic material in question has a tendency to do. It’s much more complex than tampering slightly with an otherwise normal process (birth control pills are relatively minor in comparison).
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I disagree, I find that it is often used (and not at all helpfully). But that is a matter of perspective.
However I do agree with you in that “resetting” specialized adult cells can potentially offer more problems than working with cells created by “normal processes.” These problems should be the focus of ongoing research into cloning.
At the moment, we don’t know why Dolly the sheep is showing physical signs of aging in advance of her years or why cloned mice have significantly reduced lifespans.
One hypothesis - and it will take a great deal more research before we can either validate or dismiss it - is that cells are genetically programmed for a given number of cell divisions and that when we use aged cells to create a clone, many of those cell divisions have already been used up.
[quote]
An additional concern focuses on whether cellular aging will affect the ability of somatic cell nuclei to program normal development. As somatic cells divide, they progressively age, and there is normally a defined number of cell divisions that can occur before senescence. Thus, the health effects for the resulting liveborn, having been created with an “aged” nucleus, are unknown.
[quote]
from The Genetics and Public Policy Center.
The problems we are seeing now in mammalian clones could be due to the use of aged cells, they could be due to the cloning process itself, or they could be due to some other factor which we haven’t yet considered. We simply don’t have enough living clones at the moment to understand why the process often goes horribly wrong.
It may be that only embryonic cells or those of newborns are suitable for cloning - we simply aren’t going to know whether that is the case until the current mammalian clones and their offspring have lived out their natural lifespans. We aren’t going to know whether what appears to be true of other mammals is true for humans within the lifetime of anyone posting on this messageboard, unless the results are negative (ie, all human clones and/or their offspring die prematurely).
I don’t mean to minimize the complexity of the cloning process. I’m referring to the fact that we go against the original processes of nature as we know it all the time with no negative repercussions in the long run. I can remember when the first pill came out and the estrogen level was so high in them that blot clots and strokes were a fairly common occurance, then we improved upon the product while maintaining the original goal. I think we will someday discover the true cause and effect of cloning and realize it is not so unnatural after all, just different. We have a long way to go and alot of unanswered questions that make it seem unnatural at present.
reprise
Good informative link. I wasn’t offering a real solution to the accelerated aging problem with clones, as of course I don’t know what it is. I threw that comment out to dal_timgar to make a point of how scientists “might” find a solution to the problem.