Molecular Basis for the Dominant White Phenotype in the Domestic Pig
- Stefan Marklund1,4,
- James Kijas1,
- Heriberto Rodriguez-Martinez2,
- Lars Rönnstrand3,
- Keiko Funa3,5,
- Maria Moller1,
- Dirk Lange3,6,
- Inger Edfors-Lilja1,7, and
- Leif Andersson1,8
- 1Department of Animal Breeding and Genetics, Swedish University of Agricultural Sciences, Uppsala Biomedical Centre, S-75124 Uppsala, Sweden; 2Department of Obstetrics and Gynaecology, Swedish University of Agricultural Sciences, S-75007 Uppsala, Sweden; 3Ludwig Institute for Cancer Research, Uppsala Biomedical Centre, S-75124 Uppsala, Sweden
Abstract
The change of phenotypic traits in domestic animals and crops as a response to selective breeding mimics the much slower evolutionary change in natural populations. Here, we describe that the dominant white phenotype in domestic pigs is caused by two mutations in theKIT gene encoding the mast/stem cell growth factor receptor (MGF), one gene duplication associated with a partially dominant phenotype and a splice mutation in one of the copies leading to the fully dominant allele. The splice mutation is a G to A substitution in the first nucleotide of intron 17 and leads to skipping of exon 17. The duplication is most likely a regulatory mutation affecting KIT expression, whereas the splice mutation is expected to cause a receptor with impaired or absent tyrosine kinase activity. Immunocytochemistry showed that this variant form is expressed in 17- to 19-day-old pig embryos. Hundreds of millions of white pigs around the world are assumed to be heterozygous or homozygous for the two mutations.
[The EMBL accession numbers for porcineKIT1*0101, KIT1*0202, KIT2*0202, and KIT2*0101 areAJ223228–AJ223231, respectively.]
Footnotes
-
Present addresses: 4Department of Animal Science, Iowa State University, Ames, Iowa 50011 USA; 5Institute of Anatomy and Cell Biology, Göteborg University, Göteborg, Sweden; 6Department of Dermatology, Friedrich-Schiller-University of Jena, Jena, Germany; 7Department of Technology and Natural Sciences, University of Växjö, Växjö, Sweden.
-
↵8 Corresponding author.
-
E-MAIL Leif.Andersson{at}bmc.uu.se; FAX +46-18 504461.
-
- Received March 10, 1998.
- Accepted June 23, 1998.
- Cold Spring Harbor Laboratory Press
