Griffith factor is a particular material that could be picked up by a
living cell from the dead remains of its relatives and develop the
property of the same. The phenomenon is called transformation. It is now
widely used in biotechnology.
The work of Avery et al proved that Griffith factor of DNA or gene. They found DNA to be molecular basis of heredity.
Both
the discoveries indicated that DNA could be extracted from cell and
passed into another cell. Today gene transfer is being carried out in
preparation of genetically modified organisms, replacement of defective
genes (gene therapy) and production of important biochemicals.