Professor Robert Plomin talks to Jim Al-Khalili about what makes some people smarter than others and why he's fed up with the genetics of intelligence being ignored. Born and raised in Chicago, Robert sat countless intelligence tests at his inner city Catholic school. College was an attractive option mainly because it seemed to pay well. Now he's one of the most cited psychologists in the world. He specialized in behavioural genetics in the mid seventies when the focus in mainstream psychology was very much on our nurture rather than our nature, and genetics was virtually taboo. But he persisted, conducting several large adoption studies and later twin studies. In 1995 he launched the biggest longitudinal twin study in the UK, the TED study of ten thousand pairs of twins which continues to this day. In this study and in his other work, he's shown consistently that genetic influences on intelligence are highly significant, much more so than what school you go to, your teachers or home environment. If only the genetic differences between children were fully acknowledged, he believes education could be transformed and parents might stop giving themselves such a hard time.

Producer: Anna Buckley.