The origins of satins in the US come from radiation experiments decades ago; I have been told that in the UK the satins have a different origin, but I don't know what that is. US satins have a tendency to have health problems because of damage to the genes that regulate digestion, blood chemistry, and immune system weaknesses on top of those. It can be hard in some parts of the US to find healthy satins if you want to breed them. It took me several years with lots of heartbreaking problems before I found a good buck, but once I found him, I was able to eliminate most of the problems.