Researchers have discovered that Neanderthals, who lived around 50,000 years ago, were infected with three types of viruses that still affect modern humans. This finding provides the oldest evidence of human viruses to date, offering new insights into viral evolution and ancient diseases.
Oldest Human Viruses Found
The traces of these ancient viruses are approximately 20,000 years older than the previous oldest known human virus. The prior record-holder was a common-cold virus found in 31,000-year-old baby teeth in Siberia.
Method of Discovery
Scientists identified the ancient viruses by analyzing DNA sequences from the skeletons of two male Neanderthals discovered in the Chagyrskaya cave in the Altai mountains of Russia. By comparing these sequences to modern viruses, researchers confirmed that the ancient viral DNA was distinct from any contamination by modern humans or other animals.
Types of Viruses Identified
The study revealed that Neanderthals were infected with:
- Adenovirus: Known to cause cold- and flu-like symptoms, sore throat, and pink eye.
- Herpesvirus: Causes cold sores, chickenpox, and infectious mononucleosis (mono). The type found in Neanderthals resembles the one that causes cold sores.
- Papillomavirus: Can lead to genital warts and certain types of cancer.
Implications for Neanderthal Extinction
The research suggests that these viruses may have contributed to the extinction of Neanderthals around 40,000 years ago. The study’s findings were published on May 21 on the preprint server bioRxiv and have not yet undergone peer review.
Future Research and Applications
The potential to synthesize these ancient viruses for modern research could help scientists understand current diseases better. Marcelo Briones, co-senior author of the study, highlights that this discovery might lead to new medical approaches, particularly in developing vaccines and antiviral treatments.
Skepticism and Challenges
Despite the promising implications, experts express skepticism about the feasibility of reconstructing ancient viruses due to the complexity and damage to viral DNA over time. Sally Wasef, a paleogeneticist, emphasizes the current limitations in understanding and reconstructing ancient viral genomes.
Multiple Choice Questions (MCQs):
- What is the age of the Neanderthal viruses discovered by researchers?
- A) 31,000 years
- B) 50,000 years
- C) 20,000 years
- D) 40,000 years
- Where were the Neanderthal skeletons, from which the ancient viruses were discovered, found?
- A) Siberia
- B) Chagyrskaya cave
- C) Queensland
- D) São Paulo
- Which type of virus was NOT identified in the Neanderthal DNA?
- A) Adenovirus
- B) Herpesvirus
- C) Papillomavirus
- D) Influenza virus
- What symptoms can adenoviruses cause in modern humans?
- A) Cold sores
- B) Genital warts
- C) Sore throat and pink eye
- D) Chickenpox
- According to the study, what is one of the potential benefits of comparing ancient and modern viruses?
- A) To resurrect ancient viruses
- B) To improve understanding of modern diseases
- C) To cause new infections in humans
- D) To disprove viral evolution