It’s widely acknowledged that both genes and the environment play a role in the variation of people’s cognitive abilities and linking specific genes to people’s cognitive abilities has proved extremely hard. However, a brand new study published in the journal Nature Neuroscience reveals that a genetic network inside part of the brain might indeed be the genes researchers have been searching for.
As opposed to taking a look at how individual genes which could possibly be linked to certain neurological attributes, the research group from Duke-NUS Medical School and Imperial College London used a new method named Method Genetics. In this method, the researchers looked at the ways genes ‘interact’ and identify how and when other genes are switched on or off. These gene networks would show a more complex influence on a subject’s neurological behavior than independent genes ever could in isolation.
The research team started their search by studying all active genes inside the human hippocampus – a region of the brain whose function is to consolidate short-term memories into long-term memories. Because this transformation is considered as an important component of cognition, and thus hippocampus is treated as a prime location by researchers to begin their search. Using 122 frozen hippocampal samples taken from human beings displaying a variety of cognitive abilities and neurological health statuses, the researchers compared and contrasted hundreds of genes with those also found in mice.
In the research, several common networks of genes have been found – two of these networks, M1 and M3, appeared to show a specifically strong connection to human cognition, particularly the consolidation of memory. In the case of M3, it was shown to contain 150 genes that appeared to function in tandem with each other in a “convergent” network. Besides, this network would have already been active straight from birth. More importantly, this network was shown to be crucial for two extremely distinctive sorts of intelligence: crystallized intelligence and fluid intelligence. The first, crystallized intelligence, is actually a person’s ability to adapt to situations involving patterns and behaviors they have encountered before; the second, fluid intelligence, determines how well an individual can adapt to a completely new situation.
Michael Johnson, the lead author of the study, said in a statement that ‘it might be possible to work with these [networks] to modify intelligence, but that is only a theoretical possibility at the moment – we have just taken a first step along that road.’
This study is important because it changed the way neurological development is perceived. The genetic network might be considered as a football team and each gene can be considered as a single player. Even though the performance of each piece may differ, it is more important to look at the performance of the entire team.
Journal article: http://www.nature.com/neuro/journal/vaop/ncurrent/full/nn.4205.html