Extrachromosomal DNA (ecDNA)
Kartavya Desk Staff
Source: TH
Context: Extrachromosomal DNA (ecDNA) has emerged as a groundbreaking area in cancer biology, challenging foundational genetic principles and offering new insights into cancer progression and drug resistance.
About Extrachromosomal DNA (ecDNA):
• What is ecDNA?
• Definition: ecDNA is a circular fragment of genetic material that breaks away from chromosomes and floats freely in the cell nucleus. Formation: Created by DNA damage, chromosomal rearrangements, or errors during cell replication.
• Definition: ecDNA is a circular fragment of genetic material that breaks away from chromosomes and floats freely in the cell nucleus.
• Formation: Created by DNA damage, chromosomal rearrangements, or errors during cell replication.
• Where is ecDNA Found?
• Commonly present in cancer cells. Detected in 17% of tumor samples, with higher prevalence in liposarcomas, brain tumors, and breast cancers.
• Commonly present in cancer cells.
• Detected in 17% of tumor samples, with higher prevalence in liposarcomas, brain tumors, and breast cancers.
• Key Features of ecDNA
• Carries Oncogenes: Contains multiple copies of cancer-causing genes. Dynamic Interactions: Moves freely in the nucleus, forming concentrated hubs that amplify oncogene expression. Violates Mendel’s Third Law: ecDNA clusters are inherited together, preserving advantageous genetic combinations.
• Carries Oncogenes: Contains multiple copies of cancer-causing genes.
• Dynamic Interactions: Moves freely in the nucleus, forming concentrated hubs that amplify oncogene expression.
• Violates Mendel’s Third Law: ecDNA clusters are inherited together, preserving advantageous genetic combinations.
Additional info: Mendel’s law of independent assortment states that the alleles of two (or more) different genes get sorted into gametes independently of one another. In other words, the allele a gamete receives for one gene does not influence the allele received for another gene.
• Significance of the Study
• Challenges Genetic Dogma: Overturns the assumption that non-linked genes inherit independently. Accelerates Cancer Progression: Enhances tumor evolution and drug resistance by increasing oncogene activity. New Drug Development: Researchers identified BBI-2779, a CHK1-inhibiting drug, that selectively targets ecDNA-driven cancer cells, paving the way for novel treatments.
• Challenges Genetic Dogma: Overturns the assumption that non-linked genes inherit independently.
• Accelerates Cancer Progression: Enhances tumor evolution and drug resistance by increasing oncogene activity.
• New Drug Development: Researchers identified BBI-2779, a CHK1-inhibiting drug, that selectively targets ecDNA-driven cancer cells, paving the way for novel treatments.
Insta Links:
• Environmental-DNA