OMIA 001737-9793 : Coat colour, white spotting, KIT-related in Equus asinus

In other species: dog , domestic cat , Arabian camel , cattle , goat

Possibly relevant human trait(s) and/or gene(s) (MIM number): 172800

Mendelian trait/disorder: yes

Mode of inheritance: Autosomal dominant + recessive lethal

Considered a defect: no

Key variant known: yes

Year key variant first reported: 2015

Cross-species summary: Variable degree of white spotting ranging from tiny white spots up to completely white animals. The absence of pigment is caused by the absence of skin melanocytes ("leucism"), not by failure in the biochemical reactions required for pigment synthesis.

Molecular basis: Haase et al. (2015): c.1978+2T>A in a splice donor site

Fenn et al. (2017) confirmed the likely causality of the above mutation, concluding "the results of this study enhance the evidence that the previously identified variant is associated with white spotting in donkeys. Because the splice site variant was not observed in the homozygous state, this result also supports the hypothesis that homozygosity for this genetic variant is incompatible with life. The presence of the variant in donkeys of different breeds (Miniature Donkey and Mammoth Jack) suggests that the variant probably arose prior to breed separation"

Tanaka et al. (2020) provided evidence to reinforce the conclusion that "white spotting in donkeys . . . [is] less variable than in horses [being due to heterozygosity for just one variant, namely c.1978+2T>A] and support homozygosity being lethal, highlighting the caution that should be taken when mating spotted donkeys to avoid producing nonā€viable foals".

Associated gene:

Symbol Description Species Chr Location OMIA gene details page Other Links
KIT v-kit Hardy-Zuckerman 4 feline sarcoma viral oncogene homolog Equus asinus - no genomic information (-..-) KIT Homologene, Ensembl, NCBI gene

Variants

By default, variants are sorted chronologically by year of publication, to provide a historical perspective. Readers can re-sort on any column by clicking on the column header. Click it again to sort in a descending order. To create a multiple-field sort, hold down Shift while clicking on the second, third etc relevant column headers.

WARNING! Inclusion of a variant in this table does not automatically mean that it should be used for DNA testing. Anyone contemplating the use of any of these variants for DNA testing should examine critically the relevant evidence (especially in breeds other than the breed in which the variant was first described). If it is decided to proceed, the location and orientation of the variant sequence should be checked very carefully.

Breed(s) Variant Phenotype Gene Allele Type of Variant Reference Sequence Chr. g. or m. c. or n. p. Verbal Description EVA ID Year Published PubMed ID(s) Acknowledgements
Coat colour, white spotting, due to KIT KIT Ws splicing c.1978+2T>A 2015 25818843

References


Note: the references are listed in reverse chronological order (from the most recent year to the earliest year), and alphabetically by first author within a year.
2020 Tanaka, J., Grahn, R., Bellone, R.R. :
Evidence supports white spotting in donkeys as a homozygous lethal condition. Anim Genet :, 2020. Pubmed reference: 32657451. DOI: 10.1111/age.12983.
2017 Fenn, D.J., Raudsepp, T., Cothran, E.G., Hamilton, N.A., Haase, B. :
Validation of a candidate causative mutation for white spotting in donkeys. Anim Genet 48:124-125, 2017. Pubmed reference: 27611565. DOI: 10.1111/age.12494.
2015 Haase, B., Rieder, S., Leeb, T. :
Two variants in the KIT gene as candidate causative mutations for a dominant white and a white spotting phenotype in the donkey. Anim Genet :, 2015. Pubmed reference: 25818843. DOI: 10.1111/age.12282.

Edit History


  • Created by Frank Nicholas on 16 Apr 2015
  • Changed by Frank Nicholas on 16 Apr 2015
  • Changed by Frank Nicholas on 17 Oct 2016
  • Changed by Frank Nicholas on 02 Mar 2017
  • Changed by Frank Nicholas on 16 Jul 2020