Human Cloning (Geek-Alert)

[azraphael]

So I was sitting at a night-club with some friends this evening discussing literature while the Burlesque performers were practicing getting their pasties gyrating in unison back stage.

Both my friend and I had read all of Heinlein's Lazarus Long stories, however his girl-friend had never heard of them. We covered some of the back-plot including

Comments

Not a biochemist....

[piper_lightfoot]

Inherent problem with DNA, its a timed program, firing off sequences and opening specific links to operate at different times upon which time, those sequences cannot again be turned back. These "openings", if you will, leave markers of new amino acid chains and actually reconfigure the DNA strand within the new burgeoning cells that are produced when this cell divides. What we truly need is a way to turn back the genetic clock and put those "opened" sequences back in their proper place for the program to run anew!
I do think that perhaps you're on to something with extracting directly from spermatozoa. Your process circumvents the problem inherent in cloning, however I do not think your method would precicly BE cloning. Just my 2cents. =D far more intelligent people than I shall wonder at it as well.

Oh, and you should modify your turkey baster, those things can have sharp edges.

Re: Not a biochemist....

[azraphael]

From what I understand, the base-pair sequence of the DNA doesn't change. Instead there are two changes that occur to the DNA:

Chemical DNA Change: A process called DNA Methylation chemically modifies the Cytosine (the C in the G-C / A-T base-pairs). Methylation of a genes Cytosine can prevent the gene from functioning by blocking it's transcription. This chemical change is persistent across cell division - see Epigenetic Inheritance.

DNA Methylation is reversed in a process surprisingly called Demethylation. This process occurs in the development of spermatozoa prior to fertilization and the formation of the zygote.

Structural DNA Change: Histone buildup around a genes DNA results in the DNA becoming tightly bound. This tight binding limits the genes functioning by restricting its transcription. This binding is persistent across cell division - see Epigenetic InheritanceHistone binding appears to be present in the spermatozoa and in the zygote, however the spermatozoa histone appears to be 'cleaned' before the first round of cell-

Re: Not a biochemist....

[azraphael]

Blast! Genetic Recombination would cause problems with my approach. Read my main post for a more detailed description.

[iarwain]

Gather the chromosomes as a shopping list (doubling up on the X).

Right. There is the hard part. DNA sequencing usually destroys the cells and thus, extracting the genes/bits after the test is problematic, let along putting them back together into workable DNA strands.

[azraphael]

I wasn't proposing sequencing the chromosomes. Steps 2 and 3 would use a technique similar to Gel Eletrophoresis. Here's how it goes! After extracting the 15 nucleus from the spermatozoa, you have 345 chromosomes. Statistics dictate (to a probability of 99.93%) that you will have all 46 chromosomes of your donor present. The problem is they are all in one lump.

It turns out that the masses of the 23 chromosomes are relative to the number of total bases in the chromosome. As these masses vary by at least 0.6% between each chromosome-pair, the 23 chromosome pairs should separate out quite nicely in the Electrophoresis stage

[azraphael]

Blast! Genetic Recombination would cause problems with my approach. Read my main post for a more detailed description.

Slight Problem with all of the above...

[jesfine]

Mainly being that when Hama and Ish did their jiggery-pokery, they relied heavily on FM.
Which, sadly, doesn't work in our particular timeline.
I'm thinking that it's one of those things for which they visited Oz.