Polymorphism of the KAP1.1, KAP1.3 and K33 genes in Merino sheep

The wool fibre is a complex structure composed primarily of proteins from the keratin family. These proteins are responsible for the major structural and mechanical properties of the wool fibre. This study examines variation in the genes encoding key keratin (K) and keratin-associated proteins (KAP) in Merino sheep. Variation at these loci has the potential to be developed as genetic-markers associated with wool traits. This study used 1541 Merino lambs born to 40 sires sourced from three farms in the South Island of New Zealand. Polymerase chain reaction—single strand conformational polymorphism (PCR-SSCP) analysis was used to identify sequence variation in the KAP1.3 (formerly known as B2C) and K33 (formerly known as KRT1.2) genes, whereas PCR-agarose gel electrophoresis was used to identify length polymorphism in the KAP1.1 (formerly known as B2A) gene. All allelic variation was confirmed by DNA sequencing. We report three alleles at the KAP1.1 locus, nine alleles at the KAP1.3 locus and five alleles at the K33 locus of Merino sheep.