absolutely. I would hope people don't now start doing fecal transplants for treating depression, or Alzheimers, or schizophrenia. These results, interesting though they may be, are not a cure; they may not even be diagnostic.

But clearly, diet, the gut microbiome, the immune system, at the very least, are linked, and linked tightly. So it would not be surprising at all, that there's a microbiome component. But we don't know what it is; how it affects the underlying disorder, and how to approach it for treatment as of now.

And as you alluded to with "genetic risk factor"; its well possible that though there is a component of the microbiome involved in the disease; it may not be significant enough to act as a vector for treatment. Or that it is just a comorbidity. We just don't know!