Bart:
Bluestem Associates wrote:
> On Mon, 13 Mar 2000 10:03:08 -0600, E. Ann Clark wrote:
> (snip)
> I would suggest (for purposes of discussion) that we ought to consider
> certain categories of GMOs acceptable, right from the start:
>
> a) all *intra*-species transfers (snip)
>
> My logic is that there is little risk from any of these categories, the
> chief benefits being relative speed of some transfers and the avoidance
> of undesired secondary characteristics.
>
Actually, the "process" risks are the same, whether it comes from the same species
or different families. The clearest example of this is work by Bergelson, J., C.B.
Purrington, and G. Wichmann. 1998. Promiscuity in transgenic plants. Nature 395:25
(3 Sept 98) with Arabidopsis thaliana. We've discussed this before on this list.
In brief,
a. In this species, there is a naturally occurring mutation conferring
chlorosulfuron (an herbicide) resistance - note that this occurs naturally (not GE),
and it occurs in A. thaliana.
b. The authors transferred this gene using transgenic techniques into other
(nonmutant) plants of the same species. Note - this is within the same species and
the method was transgenic.
c. They found that when the gene was transferred, they did indeed confer resistance
to chlorosulfuron, but they also affected outcrossing - a completely unrelated
trait. A. thaliana is naturally a "selfing" species, with 0.3% outcrossing. After
transgenic transfer, it became an "outcrossing" species - up to 10% outcrossing if
memory serves - or a 30X enhancement.
d. The actual degree of outcrossing varied among the transgenic A. thaliana plants,
depending on just where the mutant gene landed on the chromosomes - clearly, a
process issue.
e. What else was changed? The authors are evolutionary biologists, so they looked
at outcrossing. What else could have been different? How would you even know what
to look for? That is the point - it is unpredictable, although in this specific
case, it affected a trait that would have an impact on the ease of transmission of
transgenes to cross-able relatives.
So, the closeness of the cross does not necessarily reduce the risk of 'process'
related problems. Ann
To Unsubscribe: Email majordomo@ces.ncsu.edu with the command
"unsubscribe sanet-mg". If you receive the digest format, use the command
"unsubscribe sanet-mg-digest".
To Subscribe to Digest: Email majordomo@ces.ncsu.edu with the command
"subscribe sanet-mg-digest".
All messages to sanet-mg are archived at:
http://www.sare.org/san/htdocs/hypermail
This archive was generated by hypermail 2b29 : Wed Apr 05 2000 - 20:00:27 EDT