On behalf of the Organizing Committee and Executive Committee of the 48th International Symposium on Nucleic Acids Chemistry Symposium (ISNAC 2021), I would like to invite you to ISNAC 2021 from Wednesday, November 10th to Friday, November 12th. Since ISNAC2020 was canceled, we looked for a way to gather this year in Niigata. However, the infection status of COVID-19 is hardly predictable, and we decided to have ISNAC2021 entirely online. We appreciate your understanding.

COVID-19 pandemic became unexpectedly an opportunity to tell society the importance of nucleic acid chemistry. The word "PCR," which only researchers knew a year ago, has become a word known from elementary school students to the elderly. However, the scientific understanding of PCR is still limited to those who understand nucleic acid chemistry. Nucleic acid chemistry consists of fundamentals in various research fields. Its scope expands from basic research to fusion area with other disciplines, and eventually a daily life. I feel that the social responsibility of us nucleic acid chemists is increasingly heavy.

One of the reasons for planning ISNAC in Niigata this time was to convey the importance of the research field to as many people as possible. Since ISNAC has not been held in the Niigata area so far, we aimed to create an opportunity for more researchers and students to become interested in nucleic acid chemistry. Unfortunately, we could not invite you to Niigata. But we will try to maximize the merits of online and expand the young forum to broaden the population of young students and researchers.

We have also devised hospitality unique to Niigata, so we hope that ISNAC2021 becomes an excellent opportunity for every participant to strengthen a network with many people and acquire new knowledge. I am very much looking forward to seeing you online.