The early days of a deadly virus that has run rampant in chicken populations for decades — Marek’s Disease Virus (MDV) — can now be explained thanks to DNA from 1,000-year-old chickens. A new study from an international team of researchers has determined how MDV has progressively worsened in chickens, causing a prolonged panic within the poultry industry.
In the study, published inthe journal Science, researchers from the University of Oxford and Ludwig Maximilian University of Munich compared MDV genome sequences from ancient chickens with sequences found in modern chickens. Through this comparison, they could identify the genetic alterations that have led to the elevated strength of the modern virus.
The success of this discovery, as reported in a press release, can be attributed to chicken bones that were excavated from 140 archaeological sites across Europe and the Near East. DNA from the bones confirmed that MDV existed far before it was first described in 1907 — the disease was widespread in European chickens at least 1,000 years before this point, catapulting its origin story back to ancient times. However, analysis of these genetic sequences came with the revelation that the old strains were not nearly as powerful as current strains.
