Restriction endonucleases recognize specific sequences, typically 4 to 6 base pairs in length, in double-stranded DNA, cleaving both strands within or near this recognition site. This specificity makes them invaluable in cloning and restriction fragment length polymorphism (RFLP) experiments the controlled fragmentation of duplex DNA and in sequence studies. Sigma offers a wide selection of restriction enzymes and other commonly using modifying enzymes.
