Germline Gene therapy

[anti]

Is germline gene therapy the same as gene therapy?

What are advantages and disadvantages?

And what is the history of germline gene therapy?

Could you please give us website

Thankyou

[Dak]

cells can be divided into two classes: germ-line and somatic.

 

basically, any cells that could pass on their genetic information to the ofspring of an individual are germ-line, whereas those that can't are somatic.

 

In a male, sperm are (obviously) germ-line. testicle cells, giving rise to sperm, are also germ-line. all other cells in an adult are somatic. in a developing foetus, a stem-cell that will, at some point, give rise to testicular stem-cells is germ-line, etc.

 

germ-line gene thereapy is just gene therapy of germ-line cells.

 

It represents huge risks, in that any mistakes made in somatic gene therapy will only affect the individual 'tinkered with', whereas germ-line gene therapy will effect the individuals offspring, and their offspring, aswell. In other words, germ-line gene therapy could effectively introduce new genes into the species.

 

for this reason, germ-line gene therapy of any animal is, i believe, illegal in every country. certainly in the US and UK*.

 

Germ-line gene therapy is legal on plants, i believe.

 

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* having said that, i'm not so sure.

[zyncod]

for this reason, germ-line gene therapy of any animal is, i believe, illegal in every country. certainly in the US and UK*.

 

No, all those transgenic mice out there have been modified by germline therapy (technically: the first modified mouse is usually a chimera since it's the blastocyst that is modified and not the zygote).

[Dak]

ah, of course. and all the transgenic pigs, with more human-like hearts.

 

I knew there was a reason i was dubiouse about that. cheers.

 

(afaik, transgenic is synonymouse with chimeric)

[donkey]

chimeric and transgenic are totally different things aren't they? I thought A chimera is an organism derived from two (or more) different cell populations with different genomes whereas transgenic is just an organism that's had a gene added isn't it?

[zyncod]

I thought A chimera is an organism derived from two (or more) different cell populations with different genomes whereas transgenic is just an organism that's had a gene added isn't it?

 

You're right. A transgenic chimeric mouse does have two genomes. You insert your gene (or knock it out) in a mouse embryonic stem cell from a strain that has white fur. Then you insert that cell into a blastocyst from a mouse strain with black fur. The resulting (chimeric) mouse will have black and white fur patches. You do some breeding and backcrossing, and when you get a white-fur mouse, there's your transgenic mouse. The fur color is used simply as an easy way of seeing whether or not you have a transgenic.

[Dr. Dalek]

You're right. A transgenic chimeric mouse does have two genomes. You insert your gene (or knock it out) in a mouse embryonic stem cell from a strain that has white fur. Then you insert that cell into a blastocyst from a mouse strain with black fur. The resulting (chimeric) mouse will have black and white fur patches. You do some breeding and backcrossing, and when you get a white-fur mouse, there's your transgenic mouse. The fur color is used simply as an easy way of seeing whether or not you have a transgenic.

 

Interesting. The transgenic white cells become part of the chimeric mouses reproductive system, they probably would have at least somewhat of a presence in all of the organs and systems wouldn't they?

How do you know that the transgenic genes become passed on with the white gene. Don't reproductive cells switch their genes between chromosomes while maturing. You know the law of independent assortment?

[zyncod]

If the gonads are derived from the transgenic ES cell, then all the gametes will be transgenic; there won't be any recombination with the non-transgenic genome because that genome is in other cells. Therefore, if you get a white mouse by crossing a chimera with a black mouse, then you have a heterozygote for the transgene. If you want a homozygote, then coat color isn't going to help you anymore (due to independent assortment) but you can do the more labor intensive PCR screening.

 

Ps - I'm making the assumption here that white coat color is dominant over black coat color (which is not true - oops).