2022 Fiscal Year Annual Research Report

Molecular characterization, its mutation pattern and the molecular surveillance of SARS-CoV-2 in Hiroshima

Research Project

Project/Area Number	21K21113
Research Institution	Hiroshima University
Principal Investigator	KO KO 広島大学, 医系科学研究科(医), 助教 (80910299)
Project Period (FY)	2021-08-30 – 2023-03-31
Keywords	SARS-CoV-2 / variant screening / Sanger sequencing
Outline of Annual Research Achievements	A total of 734 samples from the confirmed cases of COVID-19 from different cities of Hiroshima during September 2020 to May 2021 had been included. Using direct sequencing by Sanger method to spike region of SARS-CoV-2 (22735bp-23532bp) with specific primer sets, the variant identification was done by the unique check point of specific mutation pattern. Out of total 734 samples, 731 sample had positive amplification (99.6%) among which 709 samples provided sequence data (96.9%). As a result, 661 samples had no mutation at target spike region (assuming wild type), 48 samples had mutations (26 were B.1.1.7 (Alpha), 7 were E484K single mutation and the rest were other types of mutation). The validation of Sanger had been performed by using 8 same samples using NGS and found 100% agreement.