I have seen mutants from(in specific order and all seeds I popped, just breeders, too maany strains to list): DJ Short, OG Raskal, Sensi, THSeeds, DNA, Bay Exclusives, Homegrown Natural Wonders, Exotic, CannaVenture, Bodhi, Seeds of Compassion, Alphakronik, Red Eye, Garden A Blaze, Gage Green, TGA and a few other I am sure I am forgetting. Not every one of those breeders had multiple mutants, but some of them had seriously high rates, some over 25%.
There are a few mutations(leaf) that we do grow out, webfoot, odd verigation, and some simple odd leaf shape mutations. OGKB is a serious mutant but feels the love.