Does RH neg blood link back to the Neanderthals?

[Emily2025]

This article, in New Scientist magazine says so, because it says that they are a "universal donor":

 

http://www.newscientist.com/article/dn16386-neanderthals-might-have-made-good-blood-donors.html

 

However, it does not specify anywhere that the blood type was rhesus negative, other than its referring to the neanderthal's blood type as a "universal donor", group O. However, only O negative is a universal donor. I could not find any other information on the web verifying that neanderthals are rhesus negative, only that 2 of them were found to have blood group O.

 

I would love to somehow find out more about this, and if they were rhesus negative or not.