Re: Count sheep, anyone?

Loren Haarsma (lhaarsma@OPAL.TUFTS.EDU)
Thu, 06 Mar 1997 14:13:03 -0500 (EST)

Thanks for your response, Brian.
You wrote:

> Loren wrote:
>> 2. Back to cloning. It is entirely possible that the procedure
>> postulated at the beginning of this letter could be modified a bit so
>> that it would *not* be possible for this procedure to produce a viable
>> embryo. (One "crude" way would be to include a retrovirus with the
>> donated DNA which would interrupt the normal developmental program at
>> some stage. There are probably subtler ways to accomplish this.) Would
>> this alter the procedure's moral status?

> If I recall correctly, retroviruses are not transcriptionally active in
> early embryos. At what point are you proposing terminating
> development? In the final analysis, what is the real difference between
> genetically programming a termination of human development and just
> destroying the human embryo outright?

IMO, there is no real difference between genetically programming the
termination of a human development and just destroying the embryo
outright. I would oppose that procedure. However, I think it is likely
that some version of this will be tried in the near future, at least in
countries which allow experimentation on in vitro embryos.

A colleague of mine suggested a variation on this. Although it is not
possible now, it may soon be possible to identify, and in certain cases
activate, the control genes for developing certain specific kinds of
tissue and organs. (More would need to be known about the external
biochemical developmental cues as well.) Suppose this "cloning"
procedure could be modified so that, instead of re-setting the *entire*
embryonic developmental program, only a certain portion of it were
activated by activating specific control genes. This could, in theory,
be done simultaneously with implanting the donor nucleus into the
enucleated egg. Now, instead of growing a whole embryo, you are growing
only a portion of an embryo, producing a specific type of tissue.
(Again, this is not possible yet, but I suspect it will be in a decade
or two.) Would someone like to critique the moral status of *this* type
of procedure?

I hope y'all think these questions are worth discussing here.

Loren Haarsma