Double Minutes

**Semantic type:** Cell or Molecular Dysfunction

**Definition:** An extrachromosomal circular DNA located in the nucleus that is relatively small in size and contains chromatin but lacks a centromere and telomeres. These circular DNAs are found in tumor cells and are able to replicate during cell division during chromosome replication. They often contain extra copies of oncogenes and/or genes involved in drug resistance and lack transcription regulatory elements. Unregulated expression of genes present in these structures may play a role in tumor growth and tumor cell survival.

**Synonyms:** - DM - Double Minute Chromosome