Two variants in the KIT gene as candidate causative mutations for a dominant white and a white spotting phenotype in the donkey.
Abstract: White spotting phenotypes have been intensively studied in horses, and although similar phenotypes occur in the donkey, little is known about the molecular genetics underlying these patterns in donkeys. White spotting in donkeys can range from only a few white areas to almost complete depigmentation and is characterised by a loss of pigmentation usually progressing from a white spot in the hip area. Completely white-born donkeys are rare, and the phenotype is characterised by the complete absence of pigment resulting in pink skin and a white coat. A dominant mode of inheritance has been demonstrated for spotting in donkeys. Although the mode of inheritance for the completely white phenotype in donkeys is not clear, the phenotype shows similarities to dominant white in horses. As variants in the KIT gene are known to cause a range of white phenotypes in the horse, we investigated the KIT gene as a potential candidate gene for two phenotypes in the donkey, white spotting and white. A mutation analysis of all 21 KIT exons identified a missense variant in exon 4 (c.662A>C; p.Tyr221Ser) present only in a white-born donkey. A second variant affecting a splice donor site (c.1978+2T>A) was found exclusively in donkeys with white spotting. Both variants were absent in 24 solid-coloured controls. To the authors' knowledge, this is the first study investigating genetic mechanisms underlying white phenotypes in donkeys. Our results suggest that two independent KIT alleles are probably responsible for white spotting and white in donkeys.
© 2015 Stichting International Foundation for Animal Genetics.
Publication Date: 2015-03-27 PubMed ID: 25818843DOI: 10.1111/age.12282Google Scholar: Lookup
The Equine Research Bank provides access to a large database of publicly available scientific literature. Inclusion in the Research Bank does not imply endorsement of study methods or findings by Mad Barn.
- Journal Article
- Research Support
- Non-U.S. Gov't
Summary
This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.
The study discusses the identification of two variants in the KIT gene that could potentially be the cause for the white spotting and completely white phenotypes observed in donkeys. This research represents the first of its kind investigating the genetic mechanisms responsible for these white phenotypes in donkeys.
About the Research
- This research was conducted due to the lack of information on the genetic aspects of white spotting in donkeys. While such investigations have been carried out intensively for horses, similar studies had not been done on donkeys.
- The white spotting in question refers to areas of white or almost completely depigmented regions on a donkey’s skin. These usually progress from a white spot in the hip area.
- They also studied completely white donkeys characterized by a complete absence of pigmentation, leading to pink skin and a white coat.
- While spotting in donkeys follows a dominant mode of inheritance, the inheritance method of the completely white phenotype is unclear, but it shows similarities with dominant white in horses.
Investigation on the KIT Gene
- Aiming to discover more about the genetic mechanisms responsible for these phenotypes, the researchers decided to focus on the KIT gene. Known for causing various white phenotypes in horses, it seemed a viable candidate for investigation in donkeys.
- A mutation analysis of all 21 KIT exons confirmed the researchers’ supposition. They found a missense variant in exon 4 present only in a white-born donkey.
- Additionally, another variant affecting a splice donor site was found only in donkeys with white spotting.
- Both of these genetic variances were absent in 24 solid-coloured control donkeys, reaffirming their potential role as causes for their respective phenotypes.
Results and Future Research
- The findings of this research suggest that two separate KIT alleles are probably responsible for white spotting and white phenotypes in donkeys.
- However, further research is needed to fully understand these genetic mechanisms and validate these initial findings.
Cite This Article
APA
Haase B, Rieder S, Leeb T.
(2015).
Two variants in the KIT gene as candidate causative mutations for a dominant white and a white spotting phenotype in the donkey.
Anim Genet, 46(3), 321-324.
https://doi.org/10.1111/age.12282 Publication
Researcher Affiliations
- Faculty of Veterinary Science, University of Sydney, Sydney, 2006, NSW, Australia.
MeSH Terms
- Alleles
- Animals
- DNA Mutational Analysis
- Equidae / genetics
- Exons
- Genes, Dominant
- Hair Color / genetics
- Inheritance Patterns
- Mutation, Missense
- Phenotype
- Proto-Oncogene Proteins c-kit / genetics
- RNA Splice Sites / genetics
Citations
This article has been cited 7 times.- Xi Y, Xu Q, Huang Q, Ma S, Wang Y, Han C, Zhang R, Wang J, Liu H, Li L. Genome-wide association analysis reveals that EDNRB2 causes a dose-dependent loss of pigmentation in ducks. BMC Genomics 2021 May 25;22(1):381.
- Korablev A, Lukyanchikova V, Serova I, Battulin N. On-Target CRISPR/Cas9 Activity Can Cause Undesigned Large Deletion in Mouse Zygotes. Int J Mol Sci 2020 May 20;21(10).
- Alhaddad H, Alhajeri BH. Cdrom Archive: A Gateway to Study Camel Phenotypes. Front Genet 2019;10:48.
- Holl H, Isaza R, Mohamoud Y, Ahmed A, Almathen F, Youcef C, Gaouar S, Antczak DF, Brooks S. A Frameshift Mutation in KIT is Associated with White Spotting in the Arabian Camel. Genes (Basel) 2017 Mar 9;8(3).
- Strain GM. The Genetics of Deafness in Domestic Animals. Front Vet Sci 2015;2:29.
- Zhu Q, Khan MZ, Jing Y, Geng M, Zhang X, Zheng Y, Cao X, Peng Y, Wang C. The Donkey Genome: From Evolutionary Insights to Sustainable Breeding Strategies. Animals (Basel) 2025 Dec 29;16(1).
- Liu X, Peng Y, Zhang X, Wang X, Chen W, Kou X, Liang H, Ren W, Khan MZ, Wang C. Coloration in Equine: Overview of Candidate Genes Associated with Coat Color Phenotypes. Animals (Basel) 2024 Jun 17;14(12).
Use Nutrition Calculator
Check if your horse's diet meets their nutrition requirements with our easy-to-use tool Check your horse's diet with our easy-to-use tool
Talk to a Nutritionist
Discuss your horse's feeding plan with our experts over a free phone consultation Discuss your horse's diet over a phone consultation
Submit Diet Evaluation
Get a customized feeding plan for your horse formulated by our equine nutritionists Get a custom feeding plan formulated by our nutritionists
