HORTICULTURE

Detailed explanation-1: -The three principal methods used for the creation of transgenic animals are DNA microinjection, embryonic stem cell-mediated gene transfer and retrovirus-mediated gene transfer.

Detailed explanation-2: -’ The answer is not so straightforward; however, some of the reasons are to (1) study the genetic control of physiological systems, (2) build genetic disease models, (3) improve animal production traits, and (4) produce new animal products.

Detailed explanation-3: -The most common method for producing transgenic animals is gene transfer by DNA microinjection, which involves the following steps: DNA containing the desired transgene is identified and cloned (copied tens of thousands of times in bacteria) before insertion into the animal host.

Detailed explanation-4: -To generate a transgenic line, the progeny are bred with other transgenic children. Complete answer : DNA microinjection, embryonic stem cell-mediated gene transfer, and retrovirus-mediated gene transfer are the three main ways for creating transgenic animals.