Prof. M. Sekine has developed a number of innovative methods for the chemical synthesis of DNA and RNA, has created new functional nucleic acids useful for gene diagnosis and gene therapy, and has greatly contributed to this field as a leading chemist. He has succeeded in synthesizing 42 RNA fragments of Hop-Stunt viroid, m⁷G capped mRNAs, a mRNA 52mer cordoning a hormone gene, branched RNAs having a lariat structure, U-turn structures of tRNA, and 2'-O-phosphorylated RNAs of TMV RNAΩ , and the 5'-terminal site of U1snRNA. In addition, Prof. Sekine developed an excellent method for the synthesis of DNA/RNA, with a high O-selectivity of 99.7% and without protection of the base residues. He reported an effective strategy using 2-cyanoethyl as the smallest protecting group that enabled the synthesis of RNAs with much improved coupling efficiency. Furthermore, he discovered that 2'-O-cyanoethylated RNAs, the synthetic intermediates, showed better hybridization affinity for DNA or RNA. He also created oligonucleotides incorporating elaborately designed N-protected bases still capable of base-pair formation to the opposite bases, which overturned prevailing attitudes. These spectacular achievements are determined to be worthy of The CJS Award.