Clones

[Mystical]

Hey, thanks for the picture! But, I must continue to say that clones and twins are different. An "almost identical" process is not an identical process. In twins, the zygote has two sets of chromosomes (from sperm and egg). In clones, both sets of chromosomes come from a donor somatic cell (the egg cell's nucleus is removed and replaced with the nucleus of a somatic cell [which already has two sets of chromosomes]). There are more adjustments which must be "performed" after that to get the egg cell to behave/perform/become like a normal zygote. I guess that's what I mean by "used" DNA. It isn't the same as starting off "fresh."

[Believer]

Identical twins are clones of each other, what are the implications of this?

No, they are not clones. A clone is one that exhibits all traits of its primary source, all of it. Cloning is the same as duplicating. You are making more of the same exact thing. Identical twins would have to have the exact DNA structure, all the same little and big things that are made of their other twin. They would have to be the same on the inside as well as the outside, they are not clones, unless they meet these requirements.

Brian Identical twins do have the same DNA.
http://ask.yahoo.com/20010213.html
http://www.genetree.com/product/twin-dna-testing.asp

BGood, do clones (duplications) have all the same things inside and out, is a mole in the same place as their twin? Is there hair count the same number as their twin, etc.... I'm talking physical things from birth that would make them so identical that they exceed that of a twin. And I was talking also about more than DNA. Think back to the movie "The 6th Day".

[sandy_mcd]

I would agree with you, Mystical. There does seem to be a big difference between natural cloning (or identical twins) and artificial cloning. In the latter case, there is a lot of manipulation and handling which must occur. There appear to be many opportunities for error and problems. From the first Google hit on cloning:

Reproductive Cloning

Reproductive cloning is a technology used to generate an animal that has the same nuclear DNA as another currently or previously existing animal. Dolly was created by reproductive cloning technology. In a process called "somatic cell nuclear transfer" (SCNT), scientists transfer genetic material from the nucleus of a donor adult cell to an egg whose nucleus, and thus its genetic material, has been removed. The reconstructed egg containing the DNA from a donor cell must be treated with chemicals or electric current in order to stimulate cell division. Once the cloned embryo reaches a suitable stage, it is transferred to the uterus of a female host where it continues to develop until birth.

Dolly or any other animal created using nuclear transfer technology is not truly an identical clone of the donor animal. Only the clone's chromosomal or nuclear DNA is the same as the donor. Some of the clone's genetic materials come from the mitochondria in the cytoplasm of the enucleated egg. Mitochondria, which are organelles that serve as power sources to the cell, contain their own short segments of DNA. Acquired mutations in mitochondrial DNA are believed to play an important role in the aging process.

Dolly's success is truly remarkable because it proved that the genetic material from a specialized adult cell, such as an udder cell programmed to express only those genes needed by udder cells, could be reprogrammed to generate an entire new organism. Before this demonstration, scientists believed that once a cell became specialized as a liver, heart, udder, bone, or any other type of cell, the change was permanent and other unneeded genes in the cell would become inactive. Some scientists believe that errors or incompleteness in the reprogramming process cause the high rates of death, deformity, and disability observed among animal clones.

[Mystical]

Thank-you, sandy, I didn't know all that. But, I think, that when they eventually fix all these issues, clones still won't be viable.

[BGoodForGoodSake]

Hey, thanks for the picture! But, I must continue to say that clones and twins are different. An "almost identical" process is not an identical process. In twins, the zygote has two sets of chromosomes (from sperm and egg). In clones, both sets of chromosomes come from a donor somatic cell (the egg cell's nucleus is removed and replaced with the nucleus of a somatic cell [which already has two sets of chromosomes]). There are more adjustments which must be "performed" after that to get the egg cell to behave/perform/become like a normal zygote. I guess that's what I mean by "used" DNA. It isn't the same as starting off "fresh."

Sperm enters an egg and this union is called a zygote.
The zygote begins dividing into more and more cells.
A twin is formed when a zygote splits into two.

[BGoodForGoodSake]

BGood, do clones (duplications) have all the same things inside and out, is a mole in the same place as their twin? Is there hair count the same number as their twin, etc.... I'm talking physical things from birth that would make them so identical that they exceed that of a twin. And I was talking also about more than DNA. Think back to the movie "The 6th Day".

No, a clone develops from a single egg just as we all did. It would just be a younger twin.

[AttentionKMartShoppers]

BGood, enough

Clone:

#
# An organism descended asexually from a single ancestor, such as a plant produced by layering or a polyp produced by budding.

Twins are produced sexually...or must your wife talk to you about the birds and the bees? (Again)

[BGoodForGoodSake]

BGood, enough

Clone:

#
# An organism descended asexually from a single ancestor, such as a plant produced by layering or a polyp produced by budding.

Twins are produced sexually...or must your wife talk to you about the birds and the bees? (Again)

A zygote is produced by a union of sex cells.
Twins result from the cleaving of a zygote.
http://web.mit.edu/afs/athena/user/j/g/ ... ntwin.html

[AttentionKMartShoppers]

I don't care, it doesn't make them clones. They were not formed asexually!

[Mystical]

Mystical wrote:

Hey, thanks for the picture! But, I must continue to say that clones and twins are different. An "almost identical" process is not an identical process. In twins, the zygote has two sets of chromosomes (from sperm and egg). In clones, both sets of chromosomes come from a donor somatic cell (the egg cell's nucleus is removed and replaced with the nucleus of a somatic cell [which already has two sets of chromosomes]). There are more adjustments which must be "performed" after that to get the egg cell to behave/perform/become like a normal zygote. I guess that's what I mean by "used" DNA. It isn't the same as starting off "fresh."

BGood repeated:

Sperm enters an egg and this union is called a zygote.
The zygote begins dividing into more and more cells.
A twin is formed when a zygote splits into two.

Why are you repeating yourself? Not changing anything.

A clone is not a "younger" twin. The differences have been explained to you.

[BGoodForGoodSake]

Mystical wrote:

BGood repeated:

Sperm enters an egg and this union is called a zygote.
The zygote begins dividing into more and more cells.
A twin is formed when a zygote splits into two.

Why are you repeating yourself? Not changing anything.

A clone is not a "younger" twin. The differences have been explained to you.

Sorry just pointing out that twining occurs after union of sex cells. Theoretically I could contunue dividing the zygote and make more and more identical twins.

Yes there is definately a difference between cloning and twinning but it goes beyond just the union of sexual cells.

[Believer]

BGood, a clone would have to be an EXACT copy of it's primary source. I mean EXACTLY the same in everything both inside and outside the body from birth. The fact that they ARE NOT, means they are produced in a different way than twins but are still different.

[Mystical]

I know. That's the reason why I started this thread.