I think you can trace their origins to a certain region (the major lines/headliners) but once they become popular they are pretty much everywhere. Maybe slightly heavier in their home turf but overall I doubt anyone family will dominate another in a certain region.

One of the jokes around the NC way is, "you can step out your door, throw a rock and pretty much hit a Garner bred dog". With a second glance those type dogs are all over the country.

I think popularity and success twist and re-shape any original boundaries. EWO