I was wondering if anyone knew the name of the disease that when you are born you age very slowly. And I think you don't live very long if you have it. You look 12 but you really are 25 or something like that just an example. Please helpppp!!

Turner's syndrome?

I don't know if this is it
I don't think it is because I have heard of it before and this seems different than what I am thinking of
diseases Tay-Sachs disease - Google Search (http://www.google.com/search?ie=UTF-8&oe=UTF-8&sourceid=navclient&gfns=1&q=diseases+similar+to+Tay-Sachs+disease)