Fig. 3.

Evolution of the Dominant white (DW) allele at the KIT locus in pigs. (A) Large white piglet with the DW phenotype. Image credit: Per Jensen (Linköping University, Linköping, Sweden). (B) Illustration of the evolution of the DW allele from the wild-type (WT) allele involving three steps: 1) a 450-kb duplication encompassing the entire KIT gene and flanking regions, 2) one or more smaller duplications of noncoding sequence (SI Appendix, Table S2), and 3) splice mutation resulting in exon skipping of exon 17 that encodes the tyrosine kinase domain in one of the two KIT copies.