I.down1[美 daʊn, 英 daʊn]副down often appears as the second element of certain verb structures in English (back down, clamp down, tone down, etc). For translations, see the relevant verb entry (back, clamp, tone, etc).
If the duplicated region has genes that are responsible for Down syndrome physical and mental characteristics, such individuals will show those characteristics.
Indeed, researchers have found that in those with Down syndrome the amplitude of the self-evoked response actually exceeded that of the machine-evoked potential.