To reach this conclusion, scientists have reviewed almost every twin study conducted in the last 50 years. The research included data from 14,558,903 pairs of twins, measuring 17,804 individual traits across 2,748 separate publications.
Dr Beben Benyamin, one of the study's authors, said:
"There has still been conjecture over how much variation is caused by genetics and how much is caused by environmental factors — what people call nature versus nurture.Dr Benyamin explained the study's results:
We wanted to resolve that by revisiting almost all the genetic twin studies conducted over the past 50 years, and comparing all of them together.
"...there is overwhelming evidence that both genetic and environmental factors can influence traits and diseases.
What is comforting is that, on average, about 50 per cent of individual differences are genetic and 50 per cent are environmental.
The findings show that we need to look at ourselves outside of a view of nature versus nurture, and instead look at it as nature and nurture."