title: A Frameshift Mutation in KIT is Associated with  White Spotting in the Arabian Camel.
abstract: While the typical Arabian camel is characterized by a single colored coat, there are rare populations with white spotting patterns. White spotting coat patterns are found in virtually all domesticated species, but are rare in wild species. Theories suggest that white spotting is linked to the domestication process, and is occasionally associated with health disorders. Though mutations have been found in a diverse array of species, fewer than 30 genes have been associated with spotting patterns, thus providing a key set of candidate genes for the Arabian camel. We obtained 26 spotted camels and 24 solid controls for candidate gene analysis. One spotted and eight solid camels were whole genome sequenced as part of a separate project. The spotted camel was heterozygous for a frameshift deletion in KIT (c.1842delG, named KITW1 for White spotting 1), whereas all other camels were wild-type (KIT+/KIT+). No additional mutations unique to the spotted camel were detected in the EDNRB, EDN3, SOX10, KITLG, PDGFRA, MITF, and PAX3 candidate white spotting genes. Sanger sequencing of the study population identified an additional five kITW1/KIT+ spotted camels. The frameshift results in a premature stop codon five amino acids downstream, thus terminating KIT at the tyrosine kinase domain. An additional 13 spotted camels tested KIT+/KIT+, but due to phenotypic differences when compared to the KITW1/KIT+ camels, they likely represent an independent mutation. Our study suggests that there are at least two causes of white spotting in the Arabian camel, the newly described KITW1 allele and an uncharacterized mutation.
authors.affiliation: Department of Animal Sciences, UF Genomics Institute, University of Florida, Gainesville, FL 32610, USA. heather.holl@ufl.edu.
authors.forename: Heather
authors.initials: H
authors.lastname: Holl
authors.affiliation: Department of Small Animal Clinical Sciences, College of Veterinary Medicine, University of Florida, Gainesville, FL 32608, USA. isazar@ufl.edu.
authors.forename: Ramiro
authors.initials: R
authors.lastname: Isaza
authors.affiliation: Department of Genetic Medicine, Weill Cornell Medical College in Qatar, Doha, Qatar. yam2012@qatarmed.cornell.edu.
authors.forename: Yasmin
authors.initials: Y
authors.lastname: Mohamoud
authors.affiliation: Department of Genetic Medicine, Weill Cornell Medical College in Qatar, Doha, Qatar. yam2012@qatarmed.cornell.edu.
authors.forename: Ayeda
authors.initials: A
authors.lastname: Ahmed
authors.affiliation: Veterinary Public Health and Animal Husbandry, College of Veterinary Medicine and Animal Resources, King Faisal University, Al-Ahsa 31982, Saudi Arabia. faisalvet@hotmail.com.
authors.forename: Faisal
authors.initials: F
authors.lastname: Almathen
authors.affiliation: Department of Biology, University of Abou Bekr Belkaïd, Tlemcen 13000, Algeria. cherifi.youcef@ymail.com.
authors.forename: Cherifi
authors.initials: C
authors.lastname: Youcef
authors.affiliation: Department of Biology, University of Abou Bekr Belkaïd, Tlemcen 13000, Algeria. suheilgaouar@gmail.com.
authors.forename: Semir
authors.initials: S
authors.lastname: Gaouar
authors.affiliation: Baker Institute for Animal Health, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA. dfa1@cornell.edu.
authors.forename: Douglas F
authors.initials: DF
authors.lastname: Antczak
authors.affiliation: Department of Animal Sciences, UF Genomics Institute, University of Florida, Gainesville, FL 32610, USA. samantha.brooks@ufl.edu.
authors.forename: Samantha
authors.initials: S
authors.lastname: Brooks
keywords: Arabian camel;  KIT;  dromedary camel;  white spotting