Thoroughbred

Pre-implantation genetic diagnosis (PGD) is a procedure used to screen embryos recovered after uterine flush to determine sex and genetic traits through DNA testing prior to implantation in the uterus.

Tobiano is a white spotting pattern characterized by white on the body that crosses the topline.

Splashed white is a variable white spotting pattern characterized by a broad blaze, extended white markings on the legs, variable white spotting on the belly, and often one or both blue eyes. Eight mutations in two different genes have been shown to cause the splashed white pattern.

Classic Roan is a white patterning coat color trait characterized by intermixed white and pigmented hairs in the body while the head, lower legs, mane, and tail remain colored.

The extension gene, or red factor, determines whether a horse will have a chestnut base coat color or a black or bay base coat color.

Dominant white is a variable white spotting pattern caused by many different mutations in the KIT gene. The VGL tests for the five most common mutations known as W5, W10, W13, W20, and W22. Homozygosity for W5, W10, W13 or W22 is thought to be non-viable.

Cream is a dilution that causes the palomino, buckskin, smoky black, cremello, perlino, and smoky cream coat colors.

The agouti gene controls the distribution of black pigment, and determines whether a horse will have a bay or black base coat color.

Fragile foal syndrome (FFS) type I, formerly known as Warmblood fragile foal syndrome (WFFS) type I, is a recessive inherited connective tissue defect characterized by hyperextensible joints and abnormally thin fragile skin and mucous membranes.