Have you noticed that people on the British Isles really love their tea and that folks in out Pacific Northwest really need their coffee? This is due to a horticultural phenomenon called “sister regions.”
The similar ocean currents that run along the northwest coasts of North America and Europe define the weather, which defines the soils, which defines the type of plant life that thrives. Those currents also create the kind of gray, drizzly weather that has any sane person reaching for some caffeine.
Ocean currents like the Gulf Stream also make the eastern U.S. and eastern Asia into sister regions. In fact, the U.S. even has a sister region comparable to the Mediterranean: wine-growing regions of California. (In Europe, it’s said that a bad year for wine is a good year for truffles.)
The upshot for truffle growers is that if you want to grow non-native truffles, you’ll have an easier time of it choosing a truffle from a sister region. The rainfall, soil pH and temperatures will be similar to what they evolved with. That means less work and expense for you.