Michael Rossi writes:

Nancy Segal’s Born Together – Reared Apart tells the story of one effort to return to hereditarian accounts: the Minnesota Study of Twins Reared Apart, or Mistra, which between 1979 and 1999 examined 137 pairs of identical and fraternal (non-identical) twins separated in early childhood and raised in different households, assessing such traits as intelligence, conservatism, personal dynamism, creativity, religiousness and sexuality. After a series of more than four thousand tests, as well as observations and interviews with the twin pairs, Mistra scientists proposed that a huge number of personality traits previously thought to be influenced by environment and upbringing – such things as career choice, reading habits, food preferences, when we have sex and whom we tell about it – were, in fact, driven by genes. ‘Behaviour[al] geneticists,’ Segal declares, ‘have shown that virtually all measured traits display genetic variation.’

(LRB7 February 2013)

Harvard University Press | Hardback 416 pp. |ISBN: 9780674055469