There's a photo knocking around purporting to show a Down's Syndrome Tiger:
I thought it was, but searching for the photo I found this:
Speaking as person who worked where Kenny lived out his years he does NOT have Down Syndrome. His parents were both white tigers as well as being brother and sister and his previous owner was breeding them together to produce more white tigers he could sell for a profit. When Kenny was born he was deformed due to poor genetics and so the owner was going to put him and his brother Willy (who was an orange tiger with crossed eyes) down but Turpentine Creek Wildlife Refuge stepped in and rescued the whole family. They all lived out the rest of their lives running around on grass and enjoying a chance to be 'wild'. Kenny's mother is the only surviving member of the family. Kenny was a great tiger and a great reminder to those out there the effects of inbreeding tigers for a profit.