Positively charged DNG oligonucleotide mixed sequences containing A/T bases were prepared by solid-phase synthesis. Synthesis proceeds in 3′→ 5′ direction and involves coupling of 3′-Fmoc protected thiourea in the presence of HgCl2/TEA with the corresponding 5′-amine of the growing oligo chain. DNG binding characteristics with complementary DNA and with itself have been evaluated.