A colour of the horse caused by a complete, or almost complete lack of colour pigment throughout the body. This leads to pink skin, white coat colour and blue eyes. Occasionally the horse may have spots of colour remaining, sometimes over the eye, leading to brown eyes. Genetically, this colour is caused by a 'White' gene (W), which has a dominant inheritance. The homozygous form is lethal in an early embryonic stage, therefore all white horses are genetically heterozygous.  This colour is sometimes refered to as 'albinism', however it is not caused by the same gene as in other animals, and the eyes are never red as the iris always retains some pigmentation. In adult horses, it may be difficult to differentiate between a white horse, a blue-eyed creme (homozygous for the 'Creme' gene) and a few-spot leopard appaloosa.