A new study links a specific genetic mutation to a higher intelligence, with debilitating consequences
A new study links a specific genetic mutation to a higher intelligence, with debilitating consequences. (PC Sangharsh Lohakare on Unsplash).

A Genetic Mutation Can Boost Your Intelligence…But Also Cause You to Go Blind

There is no standard definition of intelligence. From book smarts to street smarts, the definition of intelligence varies from person to person. Yet, intelligence is something most people want more of and work to gain. New research from Leipzig University may have unearthed a new way to gain intelligence, in the form of a genetic mutation.

Background: Measuring Smarts

There are many different ways to measure an individual’s intelligence. The most popular test is the Intelligence Quotient (IQ) test. This test works by calculating an IQ score using a person’s mental age (how many questions they answered correctly), divided by their chronological age, and then multiplied by 100. An average IQ is 100, or when a person’s mental age is the same as their chronological age. However, there are some problems with this test, as the mental age may stop growing while the chronological age continues, lowering an older person’s IQ score. For this reason, IQ tests and other intelligence tests have been criticized, as they may not accurately measure how smart a person is.

Analysis: Smart Flies

To better understand intelligence, two researchers at the University of Leipzig looked into a genetic mutation in the human brain. This mutation affects the synapses of the brain, where brain cells talk to each other. The mutation causes blindness in individuals, but oddly enough makes them possess above-average intelligence. “It’s very rare for a mutation to lead to improvement, rather than a loss of function,” explained professor Tobias Langenhann from the University of Leipzig. To better understand this mutation, the researchers duplicated the same mutation in fruit flies, and then studied their brain’s synapses. According to Langenhan: “It was our assumption that the mutation makes patients so clever because it improves communication between the neurons which involve the injured protein. Of course, you can’t conduct these measurements on the synapses in the brains of human patients. You have to use animal models for that. 75% of genes that cause diseases for humans also exist in fruit flies.”

Replicating the mutation in the flies, the researchers studied the flies’ synapses. “We actually observed that the animals with the mutation showed an increased transmission of the information at the synapses,” said Langenhan. “This amazing effect on the fly synapses is probably found in the same or a similar way in human patients, and could explain their increased cognitive performance, but also their blindness.” Perhaps the increased intelligence caused by the mutation was to compensate for the individual’s blindness. If this is the case, it would mimic the process of sensory deprivation, where other senses are heightened when one sense is missing. 

Outlook: A New Intelligence

The researchers were excited by the results of their study. As Langenhan said: “This project beautifully demonstrates how an extraordinary model animal like the fruit fly can be used to gain a deeper understanding of human brain disease.” This study suggests a new way to study other human brain diseases, as well as possible other genetic mutations that may increase a person’s intelligence.

Kenna Castleberry is a staff writer at the Debrief and the Science Communicator at JILA (a partnership between the University of Colorado Boulder and NIST). She focuses on deep tech, the metaverse, and quantum technology. You can find more of her work at her website: https://kennacastleberry.com/