show Abstracthide AbstractThe oral microbiome is a complex ecosystem composed of diverse genetic elements, including bacterial chromosomes, viruses, plasmids, and fungal chromosomes. Recent advances in bioinformatics classify genetic elements from oral metagenomic sequences, showing the association between each genetic element and human health. However, it is suspected that there are genetic elements in the human microbiome that cannot be classified by existing knowledge, as inferred from the fact that more than half of the metagenomic genes are functionally unknown. In this study, we attempted to identify novel genetic elements in the oral microbiome involved in human health by applying long-read sequencing technology.