A PCR-amplified
DNA fragment has been
digested
with three different
restriction endonucleases (EcoRI,
Bgl II,
& MboI), singly (lanes 1-3) and in
pairwise
combination
(lanes 4-6). Comparison with a molecular weight standard (lane 7)
allows
a determination of the sizes of the fragments in the digests,
which in
turn permit an inference of the order and distances among
restriction
sites in the DNA
fragment. The logic of restriction
mapping
will be explained in
Laboratory.
