VPB 321: Animal Biotechnology (2+1)

SEPARATION OF MOLECULES

• After the sequencing reactions, the mixture of strands, all of different length and all ending on a fluorescently labelled ddNTP have to be separated.
• This is done on an acrylamide gel, which is capable of separating a molecule of 30 bases from one of 31 bases, but also a molecule of 750 bases from one of 751 bases.
• All this is done with gel electrophoresis. DNA has a negative charge and migrates to the positive side.
• Smaller fragments migrate faster, so the DNA molecules are separated on their size.