A huge international study has uncovered the strongest evidence yet for a genetic link to schizophrenia. By comparing the DNA of over 37,000 individuals diagnosed with the condition and 113,000 unaffected individuals, 108 new genetic regions have been spotlighted as playing a role in the disorder, which affects about 1 person in a hundred worldwide.
The study, published in Nature this week, is the work of a large collaborative group of scientists known collectively as the Psychiatric Genomics Consortium and based at institutions around the world. The new findings highlight important new avenues for exploring and furthering our understanding of schizophrenia.
Genes linked to the nerve transmitter chemical dopamine, which is targeted by existing anti-psychotic medications and has been implicated previously in the condition, were strongly represented.
However, more than 80 genetic regions previously not known to play a role in schizophrenia were also uncovered. These include gene sequences encoding receptors for another nerve chemical called glutamate as well as genes that control the formation of channels that govern the ingress of calcium, which can excite and also alter the connections between nerve cells.
Another exciting finding is a strong association with regions of the DNA concerned with the workings of the immune system. A number of studies in the past have hinted at a relationship between a malfunctioning immune system and schizophrenia but how the two are connected was never clear. This new finding will enable scientists to begin to explore this in more detail.
Overall, this new study lends powerful credibility to the claim that schizophrenia is a biological, organic disease, rather than purely a product of growing up in or exposure to a particular environment, as claimed by some.
It will also highlight new therapeutic targets to complement the now 60-year-old treatment approaches that are the mainstay of regular therapy.
However, realising the potential of these findings, and perhaps even using them as part of a screening test for schizophrenia or to identify individuals at risk of the disease, is still a long way off.
The difference is that now researchers have turned over a great many stones, and discovered many potential gems, in one fell swoop.