NEET BIOLOGY

Detailed explanation-1: -The first method to produce transgenic pigs, pronuclear microinjection, was originally established in mice (Brinster et al., 1981). DNA is microinjected into the pronuclei of zygotes collected from a superovulated female, and then transferred to a recipient pig by embryo transfer (Hammer et al., 1985).

Detailed explanation-2: -The earliest and still most widely used method for introducing DNA into animal cells grown in culture in the laboratory is direct uptake of DNA from the surrounding culture medium.

Detailed explanation-3: -The two basic methods to detect the presence of a gene/transgene are ELISA and PCR amplification. Both methods have already been described and are robust, although each has advantages and disadvantages. For example, ELISA detects the presence of a gene product (protein) and thus requires an expressing gene.

Detailed explanation-4: -Pronuclear DNA micro-injection has long been the most reliable method to produce transgenic pigs. Despite the ease with which transgenic pigs can be generated this technique has limitations. The DNA integrates randomly and potentially in multiple copies.