Your situation is quite complicated. It is possible that if you are 21, have spent the last three years at university in the UK and your parents have a permanent UK address that nobody will ever ask whether you've been living abroad.
It depends on whether you've ever lived in the UK and on why you were in Switzerland (were you under 18 and living with your parents? or were you working?). You'll need to contact one of the research councils directly - you can find links to them on the links page of this site or at www.hero.ac.uk.