They are mutants.
A white tiger is a striking creature. Tigers are always impressive animals, but when you take away the orange, the result is a big cat that looks like a phantom out of a dream. They seem almost magical, and yet I firmly believe that the world would be a better place if there was not a single white tiger in it.
There are only about 4,000 tigers, at most, remaining in the wild. Yet there are probably tens of thousands of captive tigers around the world (there is no official census). This would appear to make a compelling case for the existence of zoos and private collections. If tigers can survive and breed well in captivity, then perhaps more can be introduced to the wild when safe habitat becomes available. Yet that system isn’t working the way we think it does. A huge number of the captive tigers are hybrids of various subspecies and are so inbred that they will never be suitable for reintroduction to the wild. No tigers are more emblematic of this problem than white tigers.
The author’s view is that this creature is strictly for human entertainment, the result of a mutant gene that has been artificially selected through inbreeding to produce this unique animal that is not suited for the wild. They can not be re-introduced – captive bred animals can’t survive in the wild. The blame falls on Siegfried and Roy, Las Vegas entertainers, who used the tigers in their act. They are novelties, a product of genetic engineering where two copies of an extremely rare recessive gene found in Bengal tigers produce this odd coat color. The author reports, as with inbred animals of other types, they often have health problems or other defects.
Is this a good use of money? Is it ethical? This story was a new one on me. I wanted to share. Much of what is in this article is also in the wikipedia entry for white tigers.