Characterisation of Keratin-associated protein genes associated with wool traits

Abstract

Wool has unique attributes, but to compete with synthetics, the wool industry is looking for ways to improve their product. The use of gene-markers is one of improving the selection of genetically superior stock. The Keratin-associated proteins (KAPs) are believed to play a critical role in determining wool traits and they therefore are ideal candidates for the development of gene-markers. This research identified variation in five previously identified ovine KAP genes (KRTAP1-4, KRTAP5-4, KRTAP6-1, KRTAP7-1 and KRTAP8-1), and the KRTAP1-2, KRTAP6-2, KRTAP6-3, KRTAP8-2, KRTAP11-1, KRTAP13-3 and KRTAP24-1 genes as well. All of them were polymorphic. Given the diversity in KAP genes, an updated KAP nomenclature was created and is now in use globally. The impact of variation in KRTAP1-2 and KRTAP6-1 on wool traits was investigated, with variation in KRTAP1-2 being associated with Clean Fleece Weight (CFW), Greasy Fleece Weight (GFW) and yield. Variation in ovine KRTAP6-1 was found to affect wool fibre diameter associated traits. This study confirms the potential for KAP genes to serve as gene-markers for breeding for desirable wool traits.