Three Novel KIT Polymorphisms Found in Horses with White Coat Color Phenotypes

Area of Science:

• Genetics
• Animal Science
• Molecular Biology

Background:

• White spotting and coat patterning in horses can impact their value and health.
• Understanding the genetic basis of these traits is crucial for selective breeding.
• Previous cases of unexplained white patterning lacked a clear genetic explanation.

Purpose of the Study:

• To identify the genetic variants responsible for unexplained white patterning in horses.
• To elucidate the molecular mechanisms underlying depigmented coat colors.
• To aid in the breeding of horses with desired coat patterns.

Main Methods:

• Manual screening of aligned whole genome sequences from affected horses.
• Identification of three novel polymorphisms in the KIT gene.
• Confirmation using Sanger sequencing and in silico functional impact prediction.

Main Results:

• Three novel KIT variants, termed W37, W38, and W39, were identified.
• W37 was found to be completely linked with a W35 allele.
• All variants were predicted to severely impact KIT protein function, altering pigmentation pathways.

Conclusions:

• The identified KIT variants are likely causative for the observed white spotting phenotypes.
• These variants disrupt KIT protein function, leading to reduced pigmentation.
• This discovery provides a genetic explanation for unexplained white patterning in horses.