Figure 1

The first four principal components of the genomic relationship matrix. Scatterplot matrix of the first four principal components (PC1 to PC4) applied to the full dataset of 13,118 animals. Key: blue circle Romney; green square Coopworth; purple diamond Perendale; grey triangle Texel; X Other; where animals are coloured (other than grey) if more than 50% of that breed) and the symbols are filled if they are more than 90% of that breed. The proportion of variance explained by each of the components is shown on the diagonal.