As tame as puppies. Columbian tegus (including the gold phase or so-called "gold tegu") are generally completely untamable, although I have seen exceptions.
The Argentine varieties (Black and Whites, Reds, Blues) are completely different animals. They become very docile with even a minimal amount of human attention. All six of mine love being pet, are house-broken, beg for food, scratch at the door to be let in and out, etc. etc. They are also MUCH more inteligent (which probably makes them so much more tractable) and grow a great deal larger than than columbians.