you didn't answer me directly, I'm not obliged either. MTHFR (and possibly COMT) are examples where genotype directly influences nutrient absorption. when the human body is unaligned (poor nutrient absorption, improper physical engagement, etc), symptoms such as depression and mania are expected behaviour. your link is a list of similar symptoms grouped under labels. I find it more pertinent to assess individual symptoms and progress from there.

sometimes mental conditions are temporary and resolvable. sometimes mental conditions are permanent and symptom alleviation is the best option. both are true. we are assessing the interface to the entire body here, all traffic flows through this node to a certain degree. problematic traffic can be caused by an issue local to the central node, but this possibility does not exclude the potential for data to be problematic on arrival.

I'm not him, but most mental illnesses are exacerbated by excessive stress. For example depression, anxiety, and OCD. What causes stress varies person to person.

For example, consider you have inflammatory bowel disease (IBD). Some food causes you pain, discomfort, and stress. Over time, eating the wrong diet can worsen your anxiety. You might fear going out and having fun, because you have to use the bathroom too much. Then, in that sense, a diet incompatible with your genotype triggers your anxiety disorder.

Or consider a stressful job, like being in the military. That might trigger or cause PTSD. Then, later down the line, another stressful job might trigger that PTSD.