Is Intelligence Hereditary?

Robert Plomin, a deputy director of the MRC Social, Genetic and Developmental Psychiatry Center at King’s College London, responds.


Scientists have investigated this question for more than a century, and the answer is clear: the differences between people on intelligence tests are substantially the result of genetic differences. But let's unpack that sentence. We are talking about average differences among people and not about individuals. Any one person's intelligence might be blown off course from its genetic potential by, for example, an illness in childhood. By genetic, we mean differences passed from one generation to the next via DNA. But we all share 99.5 percent of our three billion DNA base pairs, so only 15 million DNA differences separate us genetically. And we should note that intelligence tests include diverse examinations of cognitive ability and skills learned in school. Intelligence, more appropriately called general cognitive ability, reflects someone's performance across a broad range of varying tests.

Genes make a substantial difference, but they are not the whole story. They account for about half of all differences in intelligence among people, so half is not caused by genetic differences, which provides strong support for the importance of environmental factors. This estimate of 50 percent reflects the results of twin, adoption and DNA studies. From them, we know, for example, that later in life, children adopted away from their biological parents at birth are just as similar to their biological parents as are children reared by their biological parents. Similarly, we know that adoptive parents and their adopted children do not typically resemble one another in intelligence.

Researchers are now looking for the genes that contribute to intelligence. In the past few years we have learned that many, perhaps thousands, of genes of small effect are involved. Recent studies of hundreds of thousands of individuals have found genes that explain about 5 percent of the differences among people in intelligence. This is a good start, but it is still a long way from 50 percent. Another particularly interesting recent finding is that the genetic influence on measured intelligence appears to increase over time, from about 20 percent in infancy to 40 percent in childhood to 60 percent in adulthood. One possible explanation may be that children seek experiences that correlate with, and so fully develop, their genetic propensities.

The ability to predict cognitive potential from DNA could prove tremendously useful. Scientists might use DNA to try to map out the developmental pathways linking genes, intelligence, the brain and the mind. In terms of practical implications, we have known for decades about hundreds of rare single-gene and chromosomal disorders, such as Down syndrome, that result in intellectual disability. Finding additional genes that contribute to intellectual disability could help us perhaps prevent or at least ameliorate these cognitive challenges.


http://www.scientificamerican.com/article/is-intelligence-hereditary/

THAT study pretty well ties in with my own observations from school and uni' over the years...

WE ALL just need to hope that at some future date, some nefarious and devious social engineering  types don't try and use such information and ideas for their own ulterior eugenics-based motives..        

WhoseYourWolfie wrote:

THAT study pretty well ties in with my own observations from school and uni' over the years...

WE ALL just need to hope that at some future date, some nefarious and devious social engineering  types don't try and use such information and ideas for their own ulterior eugenics-based motives..        

Makes me believe in genetic selection: that mother nature might be using her own form of 'TEST TUBE BABY' selection process, especially when reading some of the threads provide by our #1 mass topic provider

It's genetic to a point but it's what a child learns within the first five years that are ultra-important IMO.

eddie wrote:It's genetic to a point but it's what a child learns within the first five years that are ultra-important IMO.

I agree, that it is within these years that set the mark as to how children will grow.

clearly intellignce is inherited,,,

there are some on here that have inherited their intelligence in a straight line from the primordial gloop.....

This is why children from poor communities DO NOT have the same opportunities as children from wealthy communities. Well, it's one of the reasons.

Children raised in an unstable household in which the emphasis is on day-to-day survival, avoiding homelessness, etc. are not going to develop the same intelligence as rich kids with parents who can buy them tutors and other educational materials, plus spend time with them instead of juggling multiple part-time jobs.

Ben_Reilly wrote:This is why children from poor communities DO NOT have the same opportunities as children from wealthy communities. Well, it's one of the reasons.

Children raised in an unstable household in which the emphasis is on day-to-day survival, avoiding homelessness, etc. are not going to develop the same intelligence as rich kids with parents who can buy them tutors and other educational materials, plus spend time with them instead of juggling multiple part-time jobs.

Have a greenie.

Ben_Reilly wrote:This is why children from poor communities DO NOT have the same opportunities as children from wealthy communities. Well, it's one of the reasons.

Children raised in an unstable household in which the emphasis is on day-to-day survival, avoiding homelessness, etc. are not going to develop the same intelligence as rich kids with parents who can buy them tutors and other educational materials, plus spend time with them instead of juggling multiple part-time jobs.

I agree it can stem the groth of intelligence in some but in others you find it encourages others to excell and get out of this situation
As you know I come from a very large family and we were poor, but one thing that was abundent with a big family is help from your siblings.
A will to succeed is far greater than any start you can give someone in life, that of belief you can defeat the odds.
I think if you allow people to believe they are not intelligent when they are, just because they are born into poverty it can make them wrongly believe they are not intelligent. Its negatiive
There is a very thin line here how you deal with the disparity in poverty and how you promote to deal with this

Paul Ettinger wrote:

Ben_Reilly wrote:This is why children from poor communities DO NOT have the same opportunities as children from wealthy communities. Well, it's one of the reasons.

Children raised in an unstable household in which the emphasis is on day-to-day survival, avoiding homelessness, etc. are not going to develop the same intelligence as rich kids with parents who can buy them tutors and other educational materials, plus spend time with them instead of juggling multiple part-time jobs.

I agree it can stem the groth of intelligence in some but in others you find it encourages others to excell and get out of this situation
As you know I come from a very large family and we were poor, but one thing that was abundent with a big family is help from your siblings.
A will to succeed is far greater than any start you can give someone in life, that of belief you can defeat the odds.
I think if you allow people to believe they are not intelligent when they are, just because they are born into poverty it can make them wrongly believe they are not intelligent. Its negatiive
There is a very thin line here how you deal with the disparity in poverty and how you promote to deal with this

Actually i don’t think anyone in the UK or Australia can actually compare, Our systems still fund lower socio-economic communities better than the USA so there is not the compound impact as there is in the USA, being poor also means going to a poor school etc.
there needs to be a minimal level of security for a child to be open to education, this is why our societies have social welfare. in the USA they let children slip below that level.

Also there is raw intellect and actual competence, and to actually master something require many hours of practice/training. below a certain economic level people have to spend all their time on survival thus do not have the time to dedicate to mastering skills. it is skills that allow people to monetize their intelligence. thus the poverty cycle, too poor to develop the skills that would allow them to raise their earning power that would them give them more time to develop additional skills and raise their economic status, which in turn would give their kids a better start.

The class system in the US seems worse than the UK, with Australia being the best of the three countries tbh

yup you are right eddie...australia has no class whatsoever

Lord Foul wrote:yup you are right eddie...australia has no class whatsoever

Are you trying to provoke Veya?

would I ?

eddie wrote:The class system in the US seems worse than the UK, with Australia being the best of the three countries tbh

It's because we hardly have a welfare system at all -- despite what a Republican might claim ...