A mutation in the SLC45A2 gene causing the cremello phenotype in a Turkish wild horse

Coat color not only aids in the identification of horses but also plays a significant role in the accurate diagnosis and prevention of genetic disorders associated with specific coat colors. A wide variety of coat colors are observed phenotypically in horses, and these are determined by numerous different genes. This study aimed to determine whether a wild foal brought to Afyonkarahisar in 2017 as part of the "Wild Horse Control and Rehabilitation Project," which is affiliated with the 8th Regional Directorate of Nature Conservation and National Parks of the Ministry of Forestry and Water Affairs, exhibited the cream coat color, which is a rare phenotype among horses. Accordingly, the presence of a mutation in the 2nd exon of the SLC45A2 gene (solute carrier family 45 member 2, also known as MATP or AIM-1) was investigated. Seven Thoroughbred horses with basic dark colors (chestnut or bay) were used as a control group. The DNA sequencing analysis revealed a point mutation in the 2nd exon of the SLC45A2 gene, specifically NC_009164.3:g.31690653 G>A (rs1140980396). It was concluded that this mutation may lead to the expression of the cream gene (CCr) and the resulting cremello phenotype in wild horses, which are one of the native genetic resources of Türkiye. However, it is considered that more comprehensive and detailed studies are needed to accurately determine the phenotypic coat color variations observed in feral horses, their corresponding genotypes, and the allele frequencies within the population.