Possible to gain German citizenship?

Greetings forum,  

I have contradicting info about gaining German citizenship - and am wondering if someone here can lend some clarity.  

I was born in Frankfurt am Main in 1962 to an American father and German mother.  I have a German birth certificate and had lived in Germany for most of my childhood, then moving with my family to the US in my early teens. I now reside in the US.  

What are my chances for gaining German citizenship? Will I have to relinquish US citizenship in doing so? 

Thanking you in advance.