O o d h e a d p u b L i s h I n g L i m I t e d

1.6
Some other aspects of wool production that
could be achieved by transgenesis
A central problem of wool production is the increasing cost of the harvesting
of wool by mechanical shearing and alternative procedures have been sought
© 2009 Woodhead Publishing Limited

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Advances in wool technology
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for many years, especially biological ones. When the discovery of epidermal
growth factor (EGF) and its remarkable effect on keratinisation were reported,
wool biologists made the major finding of the dramatic effect of exogenous
EGF isolated from mouse salivary glands on wool growth (Moore et al.,
1982). It was shown that the EGF inhibited DNA synthesis in the follicle
cells that led to cell death (apoptosis) and fibre shedding (Panaretto et al.,
1984). These remarkable findings were ultimately incorporated into a
commercial procedure in which EGF is produced by factory-scale recombinant
DNA technology involving expression of the human EGF gene in bacterial
culture and purification of the factor. Although administration of a single
subcutaneously injected dose of EGF can successfully replace shearing and
is used by some wool growers, the impact on the industry has seen only