The Genetic Basis of White Tigers

Very cool article demonstrating how one tiny change to a single gene can have a huge biological effect.  In this case, only one protein was mutated to change the Bengal tiger (Panthera tigris tigris) to a white tiger! 

The change is from an alanine molecule (in red) to a valine (in green) in the SLC45A2 protein.  As you can see, this is a very small difference (circled):




The Bengal tiger makes the red molecule in its SLC45A2 gene, but the white tiger makes the green molecule in its place.