There are six known genetic disorders in Arabian horses. Two are inevitably fatal, two are not inherently fatal but are disabling and usually result in euthanasia of the affected animal; the remaining conditions can usually be treated. Three are thought to be autosomal recessive conditions, which means that the flawed gene is not sex-linked and has to come from both parents for an affected foal to be born; the others currently lack sufficient research data to determine the precise mode of inheritance. Arabians are not the only breed of horse to have problems with inherited diseases; fatal or disabling genetic conditions also exist in many other breeds, including the American Quarter Horse, American Paint Horse, American Saddlebred, Appaloosa, Miniature horse, and Belgian.