It's not quite that simple, Crystalrose. Think of it as a flow chart. First, at the top, are your grandparents. Then coming down are your parents and their brothers and sisters. Then coming down from them are their children. Then coming down from that level (or YOUR level) of relatives, are any children you or your cousins have. Now: It doesn't make sense that your aunt could pass something on to you. Her blood line doesn't go to you. But it does go to HER child. Get it? It's kinda like who's womb bore whom. And who's genes went to whom.
Also, the way neurotransmitters function in certain illnesses are not necessarily the way they act in other illnesses even though they may be the same neurotransmitter. For example, I recall talking to a young man here on PC who's doctor prescribed a dopamine reuptake inhibitor for one illness and also prescribed a dopamine production enhancer to be taken simultaneously. He was concerned that these were two medications canceling out the results of each other. I explained to him that one produced more dopamine and the other simply allowed the dopamine to remain between the nerve synapses for a longer period of time, thus enabling the messaged between neurons to be more effective. The point was, just because it was dopamine being affected by both medications didn't mean the meds were doing the same job in both instances.
I guess this is why we all aren't pdocs, eh? This is giving me a headache. How about you guys?