First, I wouldn't necessarily assume no one in your family has eds, they just might not know it. It is unlikely to have a random mutation come up in just you, but it is a possibility! Secondly, heds is the most common of all types of eds, so from a general population standpoint you are much more likely to have that instead of one of the other two. However, heds still does not have an identifiable gene that causes it, so genetic testing can only be used to see if you have a more rare form of eds. Hope it all goes well and you can get some answers!