Rudyard Kipling once asked how the leopard got its spots.
Now scientists have asked how the white tiger got, well, white.
Chinese researchers analyzed a pigment gene called SLC45A2 that is found in modern Europeans, as well as chickens and fish.
They found that the tiger carries a variation of this gene that blocks red and yellow pigments while allowing black pigments.
This means that the tigers still have their black stripes but not their rich orange color.
Sadly, white tigers have been completely removed from the wild and are now only seen in capitivity.
The tigers were extensively hunted and their habitat destroyed.
The last known white tiger in the wild was spotted in 1958.
Sightings of the tiger were first recorded in the 1500s.
"The white tiger represents part of the natural genetic diversity of the tiger that is worth conserving, but is now seen only in captivity," study author Shu-Jin Luo of China's Peking University said in a statement.
The findings were presented in the journal Current Biology.