
The conventional wisdom about how clones age is probably wrong - sohkamyung
https://www.theatlantic.com/science/archive/2017/11/dolly-sheep-clones/546614/?single_page=true
======
ChrisSD
Summary:

> Clones do have unique health problems, just not the ones that dominated
> headlines about Dolly. Clones are less likely to make it to term in
> pregnancy, and when they are born, they are more likely to be a little
> maladjusted. “You have to baby them—give them oxygen, give them glucose
> until they normalize,” says George Seidel, who studies animal-reproduction
> technologies at Colorado State University. The clones that make it to
> adulthood are generally pretty normal.

~~~
mysterypie
If you're going to quote one paragraph, I think the following is more
interesting:

" _In 1999, scientists published data suggesting Dolly’s telomeres were too
short for her age. Since then, scientists have cloned a whole menagerie of
animals: mice, horses, cattle, pigs, dogs, and so on. Studies of their
telomere lengths have turned up every possible result: Clones have shorter
telomeres, clones have longer telomeres, and clones have normal
telomeres—depending on the species or cloning technique._ "

This seems to suggest that telomeres might be much less connected with aging
than initially believed by some researchers.

------
Symmetry
It sounds like most of the problems that clones have had are epigenetic and
that they could be eliminated with better techniques.

------
lend000
There was an article on HN a few months ago claiming every neuron in a human
brain is genetically unique (my interpretation was that this was due to random
errors). So essentially, you won't be able to find a single cell to clone a
multicellular organism with any accuracy -- you would need to take a large
number and average out the variation to get a reliable estimate of the
original zygote's DNA. (And perhaps pump of telomere length as well, or make
any other adjustments that would happen consistently across cell divisions).

~~~
Symmetry
The unique mutations in your brain and immune system too are induced during
development. The body needs variation in neurons so they can recognize
themselves millimeters away and not connect with themselves. And it needs
immune cells that recognize a wider variety of proteins than could be encoded
directly in DNA. So somehow mutations are induced in specific genome regions
in the brain and immune system.

Which isn't to say that mutations don't play a large role in other cells. The
average child has at least one mutation but usually they don't do much. Well,
doesn't do much or means the zygote is totally nonviable and so never results
in a pregnancy. Having children when you're older will tend to increase the
number of mutation, especially for men where their gametes are produced
throughout their lives. A cell from, say, someone's skin will tend to have
even more mutations but that's a quantitative thing rather than a qualitative
one.

~~~
lend000
> The body needs variation in neurons so they can recognize themselves
> millimeters away and not connect with themselves.

Do you have a source for this? How would a neuron with a mutation be any
different from the outside in terms of its axons?

~~~
Symmetry
Sorry, no. I was really fascinated that the brain had all this genetic
diversity and eventually I was able to ask a neuroscientist at a party why it
was there.

------
meshr
I don’t understand how it happened that all countries banned clonning.
Ethuanasia is ok but cloning is banned. So your gov better kill you for your
taxes than allow you to reproduce more efficiently. Or is there secrete
laboratories where can I clone myself? There are less and less reasons why not
to try this.

