Are humans born with “intelligence” genes, or is human intelligence determined by environmental factors, such as economic status or easy access to education?
When a team of researchers set out to answer this question, they discovered that more than 500 genes were associated with intelligence. The results, published in Nature Genetics, indicate that intelligence is much more complex than previously thought.
How Can We Test Intelligence?
Intelligence, as defined by Merriam-Webster, is the ability to learn new information and apply it to different situations. Despite this simple definition, many elements of intelligence are difficult to nail down.
Does intelligence live in the synapses of the brain, or somewhere else entirely? The New York Times reports that psychologists have tested various mental capabilities, such as memorization and verbal skills, but test results did not definitively determine the factors behind different intelligence levels. The New York Times adds that part of the issue is that “Standard intelligence tests can take a long time to complete, making it hard to gather results on huge numbers of people. Scientists can try combining smaller studies, but they often have to merge different tests together, potentially masking the effects of genes.”
Additionally, an individual’s intelligence can be affected by various factors, such as exposure to chemicals, sickness or economic status, Vice says. Is there a better way to measure someone’s intelligence? Scientists believe that the answer lies in DNA.
Do Intelligence Genes Exist?
The University of Edinburgh recently released a statement announcing that more than 500 genes were found linked to intelligence. Harvard University partnered with the Universities of Edinburgh and Southampton to study the DNA of more than 240,000 people. The researchers determined that genes associated with intelligence could also control biological processes, with some genes even affecting longevity.
As Ian Deary of the Centre for Cognitive Ageing and Cognitive Epidemiology notes, “We know that environments and genes both contribute to the differences we observe in people’s intelligence. This study adds to what we know about which genes influence intelligence, and suggests that health and intelligence are related in part because some of the same genes influence them.”
These results, published in Molecular Psychiatry, are illuminating, but also indicate that intelligence on the genetic level is far more complicated than once assumed.
The Future of Genetic Engineering
Research into the genetic components of various traits and conditions has already reshaped medicine. Genetic tests can help women prevent diseases such as breast cancer by revealing if they have a mutation that may put them at increased risk. Prenatal or preimplantation testing helps ensure that a child won’t be born with a devastating genetic condition.
By learning which genetic mutations drive cancers, researchers have been able to use the drugs that work most efficiently to stop them, opening up a new field called precision medicine, according to the National Institute of Health.
There is even speculation that genetic engineering can improve human intelligence or produce the new evolution of superhumans.
Scientists are still learning about intelligence genes. Once they learn more, however, the applications are myriad. One fairly immediate use for this knowledge will be to create techniques that can help children’s intellectual development, with progress traceable genetically, according to The New York Times. Technology, rapidly making inroads in education, can dramatically shape what those interventions look like. Further down the line, scientists can engineer the genes, changing one or two to reduce the likelihood that someone will have a learning disability.
Before they can get there, though, there is still a lot more research to do.