Meet the Inventor  Susan Magdaleno is a Senior Staff Scientist
in the research and development department at Ambion, which is a
part of Life Technologies. Susan was asked to describe Silencer®
Select siRNA Technology. Below is a recap of her reply.  Pain
points Back when siRNAs were discovered as a technology that can
be used for general applications in the lab, there were two main
pain points.  1.  One was the efficiency of siRNA design. We
have some basic rules around how to get an siRNA that gave
pretty good efficiency. But it was really dependent on the gene
target of interest and sometimes you have to use very high
concentration levels to get that level of knockdown that is
needed for biological applications. So potency was a big issue. 
2.  The other one, which is a little more difficult to overcome,
was the idea around siRNA specificity. We could get good
designs, but sometimes they knocked down more than the target of
interest, i.e. cleaved other mRNAs with partial sequence
homology. As a result we e