The oldest human DNA sequenced to date is ancestral Denisovan DNA, retrieved from a 300,000- to 400,000-year-old human bone found in Spain's Atapuerca Mountains.
This groundbreaking discovery challenged previous understandings of early human evolution and migration patterns. It was particularly surprising because the bone was initially believed to belong to a proto-Neanderthal. The analysis, however, revealed mitochondrial DNA (mtDNA) closely related to that of the Denisovans, an extinct group of archaic humans known primarily from remains found in Siberia.
Key Takeaways:
- Source: The DNA was extracted from a hominin femur discovered at the Sima de los Huesos ("Pit of Bones") site in Atapuerca, Spain.
- Age: The bone is estimated to be between 300,000 and 400,000 years old, making its DNA the oldest hominin DNA ever sequenced at the time of the discovery.
- Unexpected Finding: The DNA was found to be more closely related to Denisovans than to Neanderthals, despite the skeletal morphology suggesting Neanderthal ancestry.
- Type of DNA: The sequenced DNA was mitochondrial DNA (mtDNA), which is passed down through the maternal line.
- Implications: This discovery complicated the understanding of the relationships between different hominin groups during the Middle Pleistocene period and raised questions about gene flow between them. It also highlights the complex history of human evolution in Eurasia.
The retrieval and analysis of this ancient DNA represent a significant technological achievement in the field of paleogenetics and contribute greatly to our understanding of the human family tree. It also emphasizes that our knowledge of the distant past is constantly evolving as new discoveries and technologies emerge.
