I don't know that it is truly helpful, and I guess it depends on what type of genetic testing you get done. Mine showed I'm a poor metabolizer of a lot of medications, which makes sense because I often need higher doses of meds (not just psych meds; meds for things like fibromyalgia as well). It showed I had a gene that made me 4 times more likely to get BP, but I am BP, so that was no shocker. And it's not an exact science. For most things, it is a combination of genes that make the difference and not just one gene, though there are some things they can link to just one gene or an area of one gene. And usually, it is just an estimation (a statistic likelihood) and not a 100% guarantee that something will be the case for you.