(A). Three, six or ten nucleotides were inserted at -81 position, between the -86/-83 and -80/-77 Ets elements of the -243mDYT1 DNA/luciferase construct giving rise to mutant constructs -243mDYT1+3C or +3G, -243mDYT1+6 and -243mDYT1+10 (B). HEK293 and N2A cells were transiently transfected with 400ng of either -243mDYT1, -243mDYT1-S1, -243mDYT1-S2, -243mDYT1+3C, -243mDYT1-3G, -243mDYT1+6, -243mDYT1+10 or pGL3 vector and 250ng pCMV-β gal. Each experiment was done in four repeats; a representative experiment out of three is shown. Bars show means ±S.E.M. of normalized luciferase activity (based on pCMV-β-gal co-transfection) over pGL3 vector. The per cent activity of each construct over the parental construct is shown above each case. Statistically significant inter-individual differences are also indicated. **= p<0.005.