Intercalation of Base Analogs
are histological stains with
planar three-ring structure that
a purine / pyrimidine
base pair. If these base
analogs slip into the DNA molecule between two
the intercalated molecule
cause DNAPol to "stutter"
copy the molecule as an
base pair. This introduces a frameshift mutation.
Ethidium bromide (EtBr ) is widely used in molecular biology as a specific dye for staining DNA: the intercalated molecule fluoresces on exposure to ultraviolet light. EtBr may be incorporated into electrophoretic gels, or the gel may be stained after running. In Bio2250 labs, care should always be taken not to expose oneself to either gels or buffer containing EtBr.