Breastfeeding IQ gene found

Scientists have identified a gene that is linked to breastfeeding and higher IQ after studying thousands of children in the UK and New Zealand.

Since the development of the IQ test it has emerged that both genetic and environmental experiences play a role in intelligence.

Now researchers from King’s College London have found that children with a particular gene who were breastfed have their intelligence raised by an average of seven IQ points.

Writing in the journal Proceedings of the National Academy of Sciences, the researchers say the finding shows that intellectual development is influenced by the interaction of people’s genes with environmental factors.

“The argument about intelligence has been about nature versus nurture for at least a century,” researcher Terrie Moffitt said. “We’re finding that nature and nurture work together.

“There has been some criticism of earlier studies about breastfeeding and IQ that they didn’t control for socioeconomic status, or the mother’s IQ or other factors, but our findings take an end-run around those arguments by showing the physiological mechanism that accounts for the difference.”

The researchers studied more than 3,000 children. Nine out of ten of the children had at least one copy of the version of the gene that yielded higher IQ when breastfed.