" It is quicker, easier and comes with the
 same caveats as the old system -- there can be off target
 changes. But these appear to be rare and innocuous. "

 I would add also quite easy to identify and eliminate in the rare instances when they happen.

It does not take very many bases to establish a unique target if you use your brain a tiny bit.   A technique called primer walking has been used in sequencing for many years now to do exactly this kind of precision identification.  Up until recently the state of the art in sequencing was limited to doing hunks only about 500 or so bases long.  So, if you wished to sequence say 2000 or 5000 bases you identified some short sequence called a primer to start with and made that primer in the lab so it would bind and then sequenced off either the 5' or 3' end of the primer.  Now you have a sequence on 500 bases.  You make a new primer that matches the end of that sequenced section and repeat the process to get the next 500 bases.  You can keep doing this until you have the total length you need.  This is so routine a high school kid could get the equipment and reagents to do it in his kitchen for a science project if he has the money to spend to get the amplified 500 base sections sequenced.  You do this technique on the whole genome.  You do not need to even know what chromosome the gene is on.

Today we are just now getting methods of doing longer hunks in one shot.  One technique using micropores that allow the DNA to go thru and count one base at a time hold the record at close to one million bases and for a some things will replace primer walking, particularly for large searches looking for potential targets or in areas loaded with longer repeats of say a few hundred to few thousand bases.  But once you have those targets you will likely go back to the 25 year old primer walking method for a whole bunch of practical reasons one of which is precision.

To say 20 or 30 bases is not enough simply shows a lack of knowledge of what has been routine in the field for years.  I am involved in doing studies using the primer walking techniques applied to whole genomes and have yet to see any matching errors happen often enough to screw up one single experiment.

But, back to Aarons point.  What the hell does GMO have to do with bees?

Dick

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