How does 16S rRNA gene sequencing contribute to understanding the human microbiome?

16S rRNA gene sequencing reads a highly conserved gene found in all bacteria, letting scientists identify microbes without growing them in a lab. By comparing the gene’s variable regions to reference databases, researchers can determine which bacterial species are present and how abundant they are in a sample. This technique lets us map the gut, skin, or oral microbiomes and track how they change with diet, disease, or treatment. For example, a study showed that people on a high‑fiber diet had more Bifidobacterium species detected by 16S sequencing, linking diet to microbiome shifts. Thus, 16S sequencing provides a quick, culture‑independent snapshot of microbial communities, helping us understand health, disease, and therapy effects.