Lethal White: Why Did My Foal Not Survive? (under construction by Stormwood)
Hunt and Jump utilizes real life genetics, which is one of the coolest parts of the game!
Lethal white is well known in frame overo horses, the lethal white overo syndrome (LWO) is the result of a mutation in the endothelin receptor B (ENDRB) gene. One copy of this particular gene will not negatively impact the offspring, but should a foal inherit a copy from each parent, they will ultimately die. In real life, not all horses that carry this lethal white gene display the typical frame markings and it is recommended that breeding animals are tested for this gene on a color panel.
If both the sire and dam have the LWO gene, there is a 25% chance that their foal would have two copies of this gene, resulting in an all white foal presenting abdominal pain and colic. These foals will die.
In Hunt and Jump, the frame gene, O, is found in the "White Markings" section of your Genetic Testing results. It is good practice not to breed two horses that both have a copy of frame- there is a 25% chance the foal will die.
*There is an exception to the rule: Should you create a horse using the Freaky Friday Herd Helper, you will have a living horse with O/O in the Genetic Testing results.
(include punnett square)
Lethal white overo is not the only form of lethal white. It is suspected that other dominant white genes can be lethal when combined. Generally speaking, dominant white genes are found on the KIT locus. (elaborate on this)
Interactions between white genes and white factor.
(include risk chart)