Association of the KRT33A (formerly KRT1.2) gene with live-weight and wool characteristics in yearling Perendale sheep

摘要

DNA samples from 691 mixed-sex Perendale sheep, born between 1998 and 2001, were typed for variation in the KRT33A gene using polymerase chain reaction - single-strand conformational polymorphism. The sheep were the progeny of two lines selected for either decreased (L), or increased (H) core bulk at yearling shearing, crosses between the lines and back-crosses. Five variants (A—E) of KRT33A were identified with a frequency of 0.07,0.04,0.07,0.35 and 0.47, respectively. The proportion of A decreasedand B increased, with a progressive increase in crimp frequency, fibre curvature and core bulk and a progressive decrease in fleece weight, staple length and washing yield with each step-wise increase in the proportion of genes derived from the H line.An effect of the presence of A on the measured wool characteristics was found, but was less than the effect with direct selection for core bulk. There was no consistent effect on body growth. While none of the variants of KRT33A were strongly predictiveof variation in core bulk, other genes on Chromosome 11 may be implicated in the differential expression of characteristics associated with core bulk.