These mice carry a spontaneous remutation at the Kit locus with homozygotes characterized by having better viability than the KitW mutants, macrocytic anemia, and a classic 'black-eyed-white' phenotype. Heterozygotes have mild, normochromic, macrocytic anemia and a white belly spot.Read More +
Kit mice possess pleiotropic defects in pigment-forming cells, germ cells, RBC's and mast cells. Heterozygous KitW-v mice produce a mid-ventral spot of variable size on the trunk, and very frequently a small mid-dorsal spot on the head as well. Homozygotes produce black-eyed white mice. KitW-v homozygotes survive significantly longer than KitW homozygotes. The inner ears of homozygotes have marked abnormalities in the cochlea (the most striking abnormalities occur in the organ of Corti and the stria vascularis) and many have severe abnormalities in the saccule as well. Female homozygotes possess very few ovarian follicles at any time and these cease to grow and develop after the age of 2 months. The lack of germ cells in mutant mice leads to the development of some ovarian tumors (mesotheliomas and granulosa cell), associated with an overproduction of pituitary gonadotropic hormone. Adult male homozygotes have abnormal testes, being almost devoid of spermatogenesis.
The viable dominant spotting mutation (KitW-v) was observed by C.C Little and A.M. Cloudman in crosses made with dominant spotting mice and reported in 1937. The mutant mice were subsequently crossed to "C57 black" mice and have been continually backcrossed to C57BL/6J since. The Jackson Laboratory production colony was obtained from the research colony of Dr. E.S.Russell in 1969.
|Allele Name||viable dominant spotting|
|Allele Synonym(s)||KitWv; W'; W2; Wv; Wv|
|Gene Symbol and Name||Kit, KIT proto-oncogene receptor tyrosine kinase|
|Strain of Origin||silvered black strain|
|Molecular Note||A C-to-T point mutation at coding nucleotide 1979 (transcript NM_021099) results in a threonine to methionine substitution at amino acid 660 (p.T660M).|
Coat color is used to determine genotypes of our C57BL/6J-KitW-v/J colony. This strain is maintained by breeding heterozygote x C57BL/6J (or reciprocal). Heterozygous (KitW-v/+) mutants have a gray with light belly and white spot, light tail and feet. The wild-type animals have a black coat color.
When using the viable dominant spotting mouse strain in a publication, please cite the originating article(s) and include JAX stock #000049 in your Materials and Methods section.