Description and Procedure:
Recombinant-DNA formation, also known as gene splicing, is a procedure whereby segments of genetic material from one organism are transferred to another. The basis of the technique lies in the use of special enzymes (restriction enzymes) that split DNA strands wherever certain sequences of nucleotides occur.
Uses or Function:
This process results in a series of donor DNA fragments that can combine with similarly formed DNA fragments from other organisms. In most experimental situations the donor DNA fragments are combined with viruses or with plasmids (small rings of self-replicating DNA found within cells). The virus or plasmid vectors carry the donor DNA fragments into cells. The combined vector and donor DNA fragment constitutes the recombinant-DNA molecule. Once inside a cell, referred to as a host, this molecule is replicated along with the host's DNA each time the host divides. These divisions produce a clone of identical cells, each having a copy of the recombinant-DNA molecule and the potential to translate the donor DNA fragment into the protein it encodes.
In 1985 a more efficient cloning procedure was developed, called POLYMERASE CHAIN REACTION (PCR), which produces two double helixes identical in composition to the original DNA sample.