Considering that Columbia Whitetails used to range in the areas we hunt Blacktails today, there is probably some shared genetic material out there still.
The Columbian white-tailed deer is the western-most subspecies of white-tailed deer which occurs throughout North America. Early records indicate that Columbian white-tailed deer were once quite numerous over its historic range, from the western slopes of the Cascade Mountains to the ocean and from Puget Sound in Washington southward to the Umpqua River Basin in southern Oregon.
Here is one from NW of Grants Pass, shot in about 1991 with a roundball, late season permit draw.