Based on how you have defined normal and abnormal, from a purely objective standpoint, no, there cannot.
Let me tell you what I say to clients when I first meet them about the word "normal". I explain that there are several words that I do not like using when conducting therapy. Normal is one of them. I explain that normal "is the cycle on a washing machine", that there is no normal except what our own experiences tell us that normal is and that is not universal. Using the term normal, unless you are using it in statistical terms, is ALWAYS a value judgment of some sort. This is why no anti-GM debater can answer the question and why I enjoy watching them squirm so much with it. They haven't figured out that arguing "normal" is a losing proposition, unless you argue it from a statistical standpoint... which doesn't suit their purposes. They want to make a value judgment, withOUT making a value judgment, which is not possible. This is why the "normal" question is such a failure and why I enjoy watching the outrage of anti-GM folks when I confront them. Their is no defense for my position on this, unless one does one of the following three things: 1) use normal in a statistical sense; 2) admit to using "normal" as a means to a value judgment; 3) admit that defining normal is context is relative to the individual. As you can see, each of these three responses are loser positions if one is trying to prove the lack of normalcy of homosexuality towards the anti-GM position. Yet, anti-GM folks STILL try to argue this. And I'll just keep forcing them to try to define it, and laughing when it sinks their position no matter how they respond.