HGG Community Forums

Your starting BCs are locked and can not be changed. You can purchase other BCs on the BC unlock page (which also has some info)

https://forest.horsegeneticsgame.com/bcUnlock.php

From the BC page
-You are only applying the physical characteristics of these breeds. Your in game breeds are not limited by any color rules that apply to real life breeds.
-Breed characteristics are not directly inheritable. Breeding two horses with the "Saddlebred" breed characteristic applied will only result in a "Saddlebred" appearing foal if the foal is born a member of a breed with the "Saddlebred" breed characteristic applied.
-Foals will never be born with a breed characteristic you don't own.
-Purchasing horses does not change their breed or breed characteristic and you may own horses with breed characteristics you have not unlocked, however their foals will not inherit any unowned breed characteristic.