Gene transfer technologies leading to transgenic animals

Gene that is introduced into the cell from an external source is called transgene. A fertile animal that carries an introduced gene (s) in its germ line is called transgenic animal. The introduction of gene (s) into animl cells that leads to the transmission of the input transgene to successive generation is called transgenesis. This article discuses and summarizes important work in the literature regarding the gene transfer technologies leading to transgenic animals. The main techniques focused in this article are DNA transfer to anmals by microinjection, biolistics and electroporation. Much stress has been given to embryonic stem cell technology, sperm-mediated gene transfer, intracytoplasmic sperm injection (ICSI), liposome/DNA delivery method, gene transfer by retrovirus and nuclear transfer method. Models for transgenic animals were also focussed. The author also reviewed the transgenic animals as bioreactors, pharmaceutical proteins derived from these animals and transgenic expression of immunoglobulin. This article will be a valuable source of information for the researcher who are starting their career in transgenic animals