Abstract

A linkage study was conducted to detect variations in the genes for keratins and keratin-associated proteins (KRTAP) that might affect wool traits. To date 93 such genes have been identified in sheep: 85 of them (~91%) are clustered in three chromosomal regions. Twenty-one genes are grouped within a 4-Mbp region on sheep chromosome 1 (OAR1), 28 within a 1-Mbp segment on chromosome 3 (OAR3), and 36 are clustered within a 1.3-Mbp site on chromosome 11 (OAR11). The DNA markers used in this work were single nucleotide polymorphisms (SNPs) dispersed throughout these keratin and KRTAP gene clusters. Markers were designed as three SNP-multiplexes: a 25-SNP, a 15-SNP and a 19-SNP multiplex for keratins/KRTAP regions on OAR1, OAR3 and OAR11, respectively. Resource animals came from eleven sire families whose progeny had been phenotyped for greasy fleece weight, washing yield, fibre curvature and diameter. Between 29 and 45 progeny per sire were genotyped with the three SNPmultiplexes. Linkage analyses on co-segregation of SNP alleles from sires with wool phenotypes of progeny were done across all the sires and within sire groups. Based on theoretical genome-wide threshold (F-value 10.13 and nominal P = 0.0016 for withinsire suggestive level), one family showed suggestive quantitative trait loci for greasy fleece weight on OAR1 and fibre diameter variability on OAR3. For these experimental animals, the results show no strong evidence of involvement of keratin and KRTAP genes in the wool characteristics analysed.

SH, Phua, DR Scobie, D O'Connell, H Henry, KG Dodds, R Brauning, and S Clerens

Proceedings of the New Zealand Society of Animal Production, Volume 75, Dunedin, , 2015