There is an interesting article and accompanying synopsis in PLoS Biology about a candidate gene for schizophrenia. The researchers actually looked for genes correlated with a schizophrenia marker called "prepulse inhibition", the phenomena in which a soft precursor noise will depress the startle reflex caused by a loud noise. Apparently, this is one of the "gating" mechanisms that our brains use to prevent sensory overload, and is disturbed in schizophrenia.
The article identifies a fatty-acid binding protein (Fabp7) as a candidate gene involved in PPI, and by inference also schizophrenia. This protein binds to docosahexaenoic acid (DHA), one of the omega-3 fatty acids that you've probably heard a lot about. There is apparently some research that indicates that doses of eicosapentaenoic acid (EPA), a precursor of DHA, may be helpful in treating schizophrenia (see this review). This, and the well-documented role of the omega-3 fatty acids in brain development and function (which is why we are all encouraged to eat fish and my baby's oatmeal has DHA added to it), make the linking of a fatty acid binding protein to schizophrenia a very nice, neat story.
The study's authors speculate whether increasing the DHA intake of pregnant women deemed at risk of having a schizophrenic child would be beneficial. This is an interesting question, which will probably be studied at some point. It is also a case of the more things change, the more things stay the same: once upon a time, over-bearing mothers were blamed for schizophrenia. Now, apparently it is mothers who don't eat enough fish.
In general, I find the data about what pregnant and nursing women should and shouldn't eat a little bit annoying. I know that this is unfair. The researchers are just trying to understand human development and also provide some advice to help women have healthier babies. However, it can be a bit overwhelming when you are trying to figure out what you should eat. No peanuts- you might cause an allergy! Is your baby gassy? Try cutting out milk products. Eat fish- Baby needs the omega-3s. Don't eat fish- it is contaminated with mercury! I think most mothers are like me. I do my best, but please don't heap on the guilt if I get something not quite right. I'm a person, too, and I have more things to do during the day than research what my optimal diet should be!