The brain's genetic secrets can be found in the blood

It turns out our blood can be used to uncover genetic secrets inside the brain, with researchers from The University of Queensland (UQ) recently using blood samples to identify gene targets for brain-related traits like IQ and diseases such as schizophrenia.

The work was led by Professor Jian Yang and Dr Ting Qi, the former of whom said this discovery will open up new avenues of research and improve scientists’ ability to unravel the complexity of brain disease.

“Identifying gene targets for brain diseases is an essential part of understanding disease risk and developing treatment and prevention strategies,” Professor Yang said.

“But the effects of individual genes on brain traits are often very small, meaning we require large sample numbers to find the gene targets, and only a few hundred brain samples are available in most databases.

“We wondered whether we could overcome this issue by using blood samples, which number in tens of thousands, to identify gene targets for brain-related complex traits and diseases.”

Together with Dr Qi and their team, Professor Yang found the local genetic controls of gene expression in the brain are very similar to those in blood. The results of their work have been published in the journal Nature Communications.

“This discovery provides strong justification for using genetic effects on gene expression estimated from blood samples as a proxy for those in the brain to boost the power of our studies to identify the genes underlying brain traits and disorders,” Dr Qi said.

“Using blood data enabled us to find 97 genes associated with IQ, schizophrenia, years of education and cigarette smoking, compared to 61 using brain data alone.”