Researchers find 40 genes that promote intelligence
How intelligent a person is depends on various factors. The genes are also responsible for this. A team of researchers has now identified around 40 genes that affect our intelligence.
Intelligence is partly hereditary
It is known that intelligence can change over the course of a lifetime. Scientists have found that the performance of the brain declines, among other things, through routine work. On the other hand, intelligent friends and families can make us smarter. Intelligence is partly hereditary. Scientists have known this for a long time. A team of researchers has now found around 40 genes that promote the development of intelligence.
Differences in intelligence can also be attributed to genetic factors
In order to arrive at their results, the scientists led by Danielle Posthuma from the Free University of Amsterdam analyzed data from various studies with a total of almost 20,000 children and almost 60,000 adults from Europe.
With the new results, almost five percent of differences in intelligence between people can be explained by known genetic factors. Overall, this is about a doubling compared to the previous state of knowledge, the researchers report in the journal "Nature Genetics".
The genetic factors include not only genes, but also tiny changes in the genome strand - so-called single nucleotide polymorphisms (SNP) - which were also discovered by the scientists.
As the dpa news agency reports, most of the genes that have now been discovered play a role in the brain, for example in the development of nerve cells.
The intelligence genes were therefore not only associated with a high level of learning success, but also with, for example, the abandonment of smoking, the brain size in childhood, autism, body size and longevity.
In contrast, there was a negative correlation with Alzheimer's, depression, schizophrenia, hyperactivity and anxiety.
Researchers disagree on the role of genetic determination
According to the experts, previous studies showed that intelligence was genetically determined 45 percent in childhood and 80 percent in adulthood.
However, not all researchers agree on the percentages. For example, the psychologist Rainer Riemann from Bielefeld University assumes 40 percent genetic determination in children and 60 percent in adults.
He also underlines the influence of external factors. "Today we know that the genes associated with intelligence do not simply develop, but that a stimulating environment is necessary so that the skills can develop," explained Riemann in the dpa report.
"If you lock someone with a full potential in a dark room, no intelligence can develop."
Little practical use
According to the information, a twin study in the USA had shown that differences in intelligence among children from socially disadvantaged families practically do not depend on genetic factors.
Only in children from privileged parents did the presumed influence of the hereditary factors manifest itself.
Elsbeth Stern from the Swiss Federal Institute of Technology in Zurich, who was not involved in the study, said, according to the dpa, that the practical sense of the study is currently still small: “Only when you can find genes from which you can reliably derive learning disorders can you do it earlier start with targeted support measures. "
But even if genetics continued to make progress, there was no reason to fear that a person's intelligence would eventually be revealed by his genes. According to Stern, intelligence is too strongly determined by the environment.
"When genetically identical seeds are planted in good or bad locations, there are also differences," says the expert.
The Bielefeld psychologist Riemann warned in the agency report against an overestimation of genetic factors.
According to him, intelligence is a necessary, but not sufficient condition for good school performance. If a normal gifted child invests a lot in learning, it also has a better chance of good school performance. (ad)