Study of mutant sheep provides exciting new opportunities

Research into “mutant” sheep has AgResearch scientists eyeing up a greater understanding of what makes human hair curly or straight, and the potential for innovative new wool products.

Commonly known as Felting Lustre mutants, these sheep are rare and share the trait of naturally occurring straight wool, instead of the usual crimped wool.

 “With these mutant sheep, we can for example look at twin lambs where one has straight wool and another crimped wool – or one animal that transforms from straight to crimped wool over time – and study the key differences,” says Scientist Jeff Plowman.

 “This can then be applied to our understanding of the differences in human hair. It’s an opportunity we would never have been able to get with human subjects.”

 The work began in 2011, when a lamb with an unusual coat was brought to the attention of AgResearch staff involved in wool research. Its appearance was so unusual that the lamb was initially thought to be a cross between a sheep and a goat. Part of this was because the lamb’s straight lustrous coat was reminiscent of an angora goat.

 Genetic testing showed it was 100 per cent sheep and its coat was the result of natural mutation.

 “As a result, we started trying to locate more of these rare sheep, so we could study what makes them different and how proteins in the wool affect the fibres,” Dr Plowman says,

 “Thanks to the assistance of farmers who came forward with these sheep, we were able to do that. We have found they show a radical change in wool structure and properties that can be tied into specific protein changes.”

 “In some cases, the mutant sheep undergo a transformation where the straight wool suddenly switches to become crimpy as they mature.”

 The curvature and diameter of the wool fibre are important properties in controlling performance in textiles and other products. For example, softness, strength and felting are all affected, but the ability to control these properties is limited because diameter and curvature are normally highly linked in sheep – low diameter means high curvature and vice versa.

 “These mutant sheep are exciting because they break the mould and give us a shot at what controls each property independently, something impossible with normal sheep,” Dr Plowman says.

 “People keep asking us if we are trying to breed the mutants themselves, but the situation is more complex than that. The mutant sheep, as lambs, have the same problem that Angora goat kids have – which is that they are a bit delicate, and probably not suitable for most New Zealand farms.”

 “We want to use what we learn to add value to New Zealand’s mainstream sheep flocks. The protein differences between the mutant sheep and semi-lustrous breeds suggest that it may be possible to breed wool with controlled levels of lustre, or crimp, independent of diameter and hence produce new wool products which allow for different market opportunities.”