They have a repository somewhere, I think it is Norway. I have a few heirlooms myself and could multiply them in a year.
I would keep a hold of them - propogate every couple of years to keep fresh stocks etc. Might be worth something one day!
Mel
It is in Norway: Svalbard
My husband was close to it recently but no one can get in, heavily guarded which is understandable.
http://www.newscientist.com/article/mg18925343.700