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The study shows that identical twins do not share
identical DNA. In about 15 per cent of identical twin pairs, one twin carried a "
" number of
that the other did not share. The scientists say this
is important as it sheds
on the "nature versus nurture" debate. This is whether human behaviour is determined by the environment, socialization and
, or by a person's genes. The research shows that this tiny
, and not environmental factors, could be the
why one twin develops different behavioural characteristics or medical
. Professor Kari Stefansson said a genetic mutation may be the
of a given disease or trait.
