Cognitive abilities directly linked to dysbindin-1

“How did she do that?” Have you ever wondered what allowed your roommate to do better than you on that particular test, even though you studied together? Don’t you just love to put all the blame on the hard test or the professor who is “clearly out to get you”? Now you could also just blame it on your genes. A recent study done at Feinstein Institute for Medical Research in Glen Oaks, N.Y., traced intelligence to a gene that seems to be a major influence on cognitive abilities.

The researchers showed that cognitive abilities are directly linked to a certain gene, dysbindin-1. It is found in key brain regions linked to cognition — specifically learning, problem solving, and judgment — as well as memory and comprehension. More than 11 previous studies have associated this gene with schizophrenia, a mental disorder that causes people to hear internal voices that other people don’t hear or to feel extremely paranoid, thinking that people are going to harm them in some way.

Researchers at the Zucker Hillside Hospital along with Harvard-Partners Center for Genetics and Genomics in Boston studied 213 patients with schizophrenia and compared them with 126 healthy volunteers. They not only studied their cognitive abilities but also examined six DNA sequences known as single-nucleotide polymorphisms (SNPs). They found one specific pattern of SNPs that was associated with general cognitive
ability, impaired in the group with schizophrenia and the healthy volunteers who were carriers of the risk variant.

“A robust body of evidence suggests that cognitive abilities, particularly intelligence, are significantly influenced by genetic factors. Existing data already suggests that dysbindin may influence cognition,” said Katherine Burdick, the study’s primary author, in a report. “We looked at several DNA sequence variations within the dysbindin gene and found one of them to be significantly associated with lower general cognitive ability in carriers of the risk variant compared with non-carriers in two independent groups.”

Scientists speculate that dysbindin-1 plays a major role in communication between neurons in the major brain areas associated with cognition. Since the gene also promotes survival of these neurons, an alteration would cause failure in protecting the neurons from dying, ultimately leading to poor intelligence and cognition.

“While our data suggests the dysbindin gene influences variation in human cognitive ability and intelligence, it only explained a small proportion of it — about three percent,” said Anil Malhotra, a principal researcher in the study. “This supports a model involving multiple genetic and environmental influences on intelligence.”