LISBON - An international team of researchers has discovered human DNA at least 2,000 years old on cave walls in Portugal and Spain, providing the first evidence that cave walls can preserve human genetic material for thousands of years.
According to a report by Lusa News Agency on Thursday, using advanced DNA extraction and sequencing techniques, the researchers detected ancient human DNA in a pigmented calcite crust from Escoural Cave in Portugal, as well as in several unpigmented cave wall samples from Escoural Cave and Covaron Cave in Spain.
The team recovered five authentic ancient human DNA samples, all dating back at least 2,000 years, the report said.
The researchers said the findings provide the first evidence that ancient human DNA can survive on cave walls for thousands of years.