Two horse heads

Horses have approximately 20,000 different genes. Each horse has two copies of every gene; one is received from the sire (male) and the other is received from the dam (female). The combination of genes that a horse has is referred to as its genotype. The characteristic that we see, such as coat color, is a result of the horse’s genotype and we refer to these characteristics as the horse’s phenotype. Some diseases are also a result of the horse’s genotype. Greater than 30 genetic disorders have been characterized in the horse to date.


Learning Objectives:

  1. Provide horse owners with basic information on equine genetics and genetic diseases commonly found in horses.
  2. Describe options for genetic disease testing in horses.


This project is supported by Agriculture and Food Research Initiative (AFRI) competitive grant no. 2009-55205-05254 from the USDA National Institute of Food and Agriculture Animal Genome Program.



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