evidence: JN.1 descended from BA.2.86, which is a sublineage of the omicron BA.2 variant, TODAY.com previously reported — that's what sets JN.1 and BA.2.86 apart from the other prevailing variants like HV.1 and EG.5, which descended from omicron XBB. BA.2.86 has more than 30 mutations compared to the omicron XBB.1.5 variant, the dominant strain for most of 2023 and the variant targeted in the updated COVID-19 vaccine, TODAY.com previously reported. "When its parent BA.2.86 emerged, everybody was worried because it had a lot of mutations and looked like it was going to evade a lot of the immunity from vaccines and infection in the population," Andrew Pekosz, Ph.D., professor and vice chair in the Department of Molecular Microbiology and Immunology at the Johns Hopkins Bloomberg School of Public Health, tells TODAY.com. "But (BA.2.86) sort of fizzled out," he adds.