Researchers at the University of Montreal in Montreal, Quebec, Canada, discovered previously unobserved mutations in the “SHANK3” gene. In a report released earlier this spring and published in the U.S. Proceedings of the National Academy of Sciences, researchers stated that people with this particular mutation may be more susceptible to schizophrenia.
What we Already Know about SHANK3
SHANK3 has been in the news before and may be better known as the “autism gene”. The results of a study released in 2006 first brought this gene into the spotlight, or more accurately, the mutations in this gene, which are present in a small percentage of people with autism. SHANK3 is part of chromosome 22.
Researchers in this study observed that in those subjects with cognitive deficits and autistic behavior, some of this gene was missing – the more significant the piece missing, the more severe the symptoms. One person studied was found to have a mild form of autism (Aspergers), and had additional copy of the gene.
The SHANK3 gene puts out a protein that, when combined with neuroligin proteins, regulates impulses sent to the brain, spinal column and nerves.
SHANK3 and Schizophrenia
The spring 2010 study out of the University of Montreal discovered two new mutations, one among three affected brothers, which suggests an inheritance of the condition. The fact that mutations in the SHANK3 gene are connected to autism, and these two new mutations to schizophrenia have led researchers to believe that there is a genetic link between the two disorders.
One of the two new mutations involved an incomplete protein (R1117X mutation), and the other a mutation identified as R536W. In both cases, the mutations were found in families of European descent.
It is hoped that identification of these mutations, and more as research continues, will lead researchers to explain and understand better how these types of conditions affect certain people and not others, and can lead to screening tests to look for these types of mutations.