Cognitive functioning certainly protected in some patients, including me

A gene has been found in some people with schizophrenia that can help protect cognitive ability.

While it may put individuals at risk for schizophrenia in the first place, schizophrenic patients with the at-risk gene performed better on certain tests of cognitive function than patients with a less risky variant of the same gene.

Dr. James T.R. Walters of the Medical Research Council for Neuropsychiatric Genetics and Genomics at Cardifff University in Wales, and his colleagues found preserved memory with a variation in the gene known as the Zinc Finger Protein 804A.

Prior research has implicated the Zinc Finger Protein 804A gene (ZNF804A) as a risk factor for schizophrenia.  Alleles are different variations of the same gene, and one allele of the ZNF804A gene seems to be more commonly present in patients with psychiatric diagnoses such as schizophrenia and bipolar disorder.  While its exact function remains elusive, some researchers suspect that the ZNF804A gene affects communication in the brain.

Walters and his team studied 297 adults with schizophrenia and 165 healthy adults in Ireland.  The same research was repeated in Germany on a population of 251 patients with schizophrenia and 1472 controls to confirm the results.

All participants were genetically tested to assess which allele of the ZNF804A gene was present.  Study participants also underwent tests of cognitive function including IQ, episodic memory, working memory, and attention.

Variations of the ZNF804A gene did not have any effect on the results of the cognitive testing in the adults with no psychiatric disorder.

However, in the individuals with schizophrenia, the at-risk allele of ZNF804A appeared to have a protective effect on cognitive functions such as working memory and episodic memory.

Walters then limited the results to only patients with a relatively higher IQ and the association between the at-risk gene and the preserved memory functions became even stronger.

“Although the observed association with cognition seem counterintuitive, it is important to note that the risk allele at ZNF804A is not so much associated with better cognitive performance in the present study as with less impaired cognitive performance,” writes Walters.

The exact nature between the relationship of ZNF804A and the development of schizophrenia is not entirely understood.  These results are important in suggesting that ZNF804A may be a risk factor for one subtype of schizophrenia, and the development of some subtypes of schizophrenia may also involve cognitive pathways.

Further research into the genetics and the molecular biology of the development of schizophrenia could provide important information to help in diagnosis, treatment and prevention of the disease.

Dr. Walter’s results can be found in the July issue of the Archives of General Psychiatry.

Source:  Archives of General Psychiatry