Cloning Genes

Gene cloning, or molecular cloning, has several different meanings to a molecular biologist. A clone is an exact copy, or replica, of something. In the literal sense, cloning a gene means to make many exact copies of a segment of a DNA molecule that encodes a gene. This is in marked contrast to cloning an entire organism—regenerating a genetically identical copy of the organism—which is technically much more difficult (with animals) and can involve ethical ramifications not associated with gene cloning. Molecular biologists exploit the replicative ability of cultured cells to clone genes.