We have previously demonstrated that SV40PolyA in antisense orientation (PolyAas,240 bp) eliminated the inhibition of GFP gene expression induced by Alu repeats,when it was placed between GFP gene and Alu repeats.Deletion analysis of PolyAas sequence suggests that a 17-bp fragment (5-AAAAAAATGCTTTATTT) is responsible for the PolyAas-activating GFP gene.