Interpretive Summary: A highly polymorphic caprine keratin-associated protein gene identified and its effect on cashmere traits

By Anne Zinn

Cashmere fiber is a main product of cashmere goats that is produced by secondary hair follicles, and, like wool, the cashmere fiber is composed of hair-keratins and keratin-associated proteins. These keratin-associated proteins serve as a matrix that cross-links hair-keratins and are therefore believed to play an important role in defining the physical and mechanical properties of the fiber. Five keratin-associated protein 6 genes (KRTAP6-5) have been identified in sheep and some variations have been associated with wool fiber diameter-related traits, but none of these homologues have been identified in goats. Given the potential effect of KRTAP6 on wool traits, investigation is needed to identify KRTAP6-n in goats and to determine whether variation in KRTAP6s affects cashmere traits. Therefore, a paper recently published in the Journal of Animal Science attempted to identify the caprine KRTAP6-5 to search for potential variation in the gene and to investigate its effect on cashmere fleece traits.

Efforts of this research reported the identification of the sheep KRTAP6-5 homologue on goat chromosome 1 and PCR-single strand conformation polymorphism analysis in 300 Longdong cashmere goats revealed the existence of 12 variant sequences. Variation in goat KRTAP6-5 was found to be associated with variation in mean-fiber diameter, suggesting that KRTAP6-5 is worthy of further study in the context of variation in cashmere traits.

The full paper can be found on the Journal of Animal Science webpage.