Found in the developing brain: Mental health risk genes and gender differences

October 26, 2011, Yale University

Most genes associated with psychiatric illnesses are expressed before birth in the developing human brain, a massive study headed by Yale University researchers discovered. In addition, hundreds of genetic differences were found between males and females as their brains take shape in the womb, the study in the Oct. 27 issue of the journal Nature shows.

The creation of a hundred billion and the incalculable number of connections between them is such a complex task that 86 percent of 17,000 studied are recruited in the effort. The study tracked not only what genes are involved in development, but where and when they are expressed, or activated.

"We knew many of the genes involved in the development of the brain, but now we know where and when they are functioning in the ," said Nenad Sestan, associate professor of neurobiology, researcher for the Kavli Institute for Neuroscience and senior author of the study. "The complexity of the system shows why the human brain may be so susceptible to psychiatric disorders."

The study identified genes expressed in the human brain, and when and where in the brain they were expressed in 1340 tissue samples taken from 57 subjects aged from 40 days after conception to 82 years. The analysis of 1.9 billion data points gives an unprecedented map of in the brain at different stages of development. In dramatic fashion, the findings show just how much of the human brain is shaped prior to birth.

For instance, the team analyzed genes and variants previously linked with autism and schizophrenia, the symptoms of which are evident in the first few years of life or during , respectively. The new analysis shows molecular evidence of expression of these suspect genes prior to birth.

"We found a distinct pattern of gene expression and variations prenatally in areas of the brain involving higher cognitive function," Sestan said. "It is clear that these disease-associated genes are developmentally regulated."

The team also looked for differences in brains of . They expected to find clear differences in Y chromosome genes that are possessed only by males. However, they also demonstrated that men and women showed distinct differences in many genes that are shared by both sexes – both in whether the gene was expressed and the level of the gene's activity. Most of the differences were noted prenatally.

Explore further: Our brains are made of the same stuff, despite DNA differences

Related Stories

Our brains are made of the same stuff, despite DNA differences

October 26, 2011
Despite vast differences in the genetic code across individuals and ethnicities, the human brain shows a "consistent molecular architecture," say researchers supported by the National Institutes of Health. The finding is ...

Autism blurs distinctions between brain regions

June 3, 2011
Autism blurs the molecular differences that normally distinguish different brain regions, a new study suggests. Among more than 500 genes that are normally expressed at significantly different levels in the front versus the ...

Young human-specific genes correlated with human brain evolution

October 18, 2011
Young genes that appeared since the primate branch split from other mammal species are expressed in unique structures of the developing human brain, a new analysis finds.

Recommended for you

Natural barcodes enable better cell tracking

April 24, 2018
Each of us carries in our genomes about 10 million genetic variations called single nucleotide polymorphisms (SNPs), which represent a difference of just one letter in the genetic code. Every human's pattern of SNPs is unique ...

The role of 'extra' DNA in cancer evolution and therapy resistance

April 23, 2018
Glioblastoma (GBM) is the most common and aggressive form of brain cancer. Response to standard-of-care treatment is poor, with a two-year survival rate of only 15 percent. Research is beginning to provide a better understanding ...

Variants in non-coding DNA contribute to inherited autism risk

April 19, 2018
In recent years, researchers have firmly established that gene mutations appearing for the first time, called de novo mutations, contribute to approximately one-third of cases of autism spectrum disorder (ASD). In a new study, ...

Natural selection still at work in humans

April 18, 2018
Evolution has shaped the human race, with University of Queensland researchers finding signatures of natural selection in the genome that influence traits associated with fertility and heart function.

Researchers discover link between gene variation and language

April 18, 2018
What shapes the basic features of a language?

Gene therapy for beta-thalassemia safe, effective in people

April 18, 2018
In a powerful example of bench-to-bedside science showing how observations made in the lab can spark life-altering therapies in clinic, an international team of clinician-investigators has announced that gene therapy for ...

1 comment

Adjust slider to filter visible comments by rank

Display comments: newest first

ArtflDgr
not rated yet Oct 27, 2011
but we are the same and have the same outcomes and all that is wrong is the fault of who programmed us...

get the zeitgeist right guys...

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.