____________________
et
al
found
abnormalities
in
genes
such
as
the
____________________
gene
which
controls
dopamine
and
serotonin
and
influences
____________________
behaviour
;
and
the
____________________
gene
which
has
been
linked
to
____________________
.
people
with
this
gene
combination
are
____________________
times
more
likely
to
have
a
history
of
violent
behaviou
r
