Umi

UMI is an acronym used in several different contexts, and its meaning depends on the field. In science and technology, UMI most commonly stands for Unique Molecular Identifier, a short, random sequence attached to individual nucleic acid molecules before amplification in sequencing experiments. The purpose of a UMI is to label original molecules so that reads arising from PCR duplication can be distinguished from true distinct molecules. This enables more accurate molecule counting and error correction, and UMIs are widely used in both single-cell and bulk sequencing workflows. Typical UMIs are about 8 to 12 bases in length and are incorporated into library adapters or primers during preparation.

In publishing and libraries, UMI historically referred to University Microfilms International, a company established to microfilm dissertations and theses. Founded in the mid-20th century by Eugene Power, UMI built a long-standing catalog of scholarly works that became a major resource for researchers. The company was later acquired by ProQuest, and its catalog was integrated into ProQuest Dissertations & Theses.

Other uses of the acronym exist in various industries and disciplines, sometimes standing for organizational names or technical concepts related to universal, unified, or user interfaces. Because UMI has multiple meanings, the intended reference is usually clarified by context.