<P> See also restriction enzymes for more detail about the enzymes exploited in this technique . </P> <P> For example the most common application of restriction mapping is presented: Determining the orientation of a cloned insert . This method requires that restriction maps of the cloning vector and the insert are already available . </P> <P> If you know of a restriction site placed towards one end of the insert you can determine the orientation by observing the size of the fragments in the gel . Often the orientation of inserts is important and this technique is used to screen for the correct orientation . </P> <P> In this example the orientation of an insert cloned with EcoRI will be found . </P>

When constructing an dna molecule what is important when determining the orientation of each strand