The basic technology is now available to undertake genetic modification in farm animals – adding new genes or modifying existing genes. However, the procedures are inefficient and costly, or lack precision, or both. The technologies also raise both welfare and ethical concerns. Thus, the traits to which this technology might be applied need to be chosen with care. High-impact traits could include enhanced resistance to disease and improvements in product quality. Genome research is revealing some of the genes controlling these and other traits and could inform the choice of genes for genetic modification.
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