there was a herd of white deer on the secured property of the Argonne Nation Laboratory.. nuclear research facility in Illinois... I believe they are gone now..
There are Albino Whitetail Deer on the former Seneca Army Depot in Romulus, NY. Right betw Seneca and Cayuga lakes.
The secured nature of the Depot grounds kept the albino/genetic species in tact for many years.
There was a protective program in effect for many years after the Depot was closed down (around 1999/2000) to try and save the habitat and area for them. But that seems to have failed.
White Deer Tours (Seneca Army Depot) | Nonprofit Organization | Seneca White Deer, Inc.
The mixed color Brown/White Piebald Whitetail Deer are not rare in WNY. But certainly they are an uncommon site.
They are called Piebald. It is due to a rare genetic variation. I've seen one in my over 50 years of hunting deer.