Genetic information has been extracted from a 1.7 million year old rhino tooth, raising hopes that crucial data about extinct animals could be retrieved, or lost species revived.
The discovery is one million years older than the oldest DNA sequenced, from a 700,000-year-old horse, and is the earliest ever recorded.
Researchers at the universities of Cambridge and Copenhagen identified an almost complete set of proteins – known as a proteome – in the dental enamel of the ancient rhino, which was found in Dmanisi in Georgia.
Proteins are molecules that carry out the major functions in the body, so studying them reveals the biology of a species. The proteome is the assortment of proteins produced by a cell or tissue, and although it is not DNA itself, it gives an idea of what genes are doing.
Prof Enrico Cappellini, a specialist in palaeoproteomics at the Globe Institute, University of Copenhagen, said: “Dental enamel is extremely abundant and is incredibly durable, which is why a high proportion of records are teeth.
“For the first time we have retrieved ancient genetic information which allows us to reconstruct molecular evolution way beyond the usual time limit of DNA preservation. This analysis will start an exciting new chapter in the study of molecular evolution.”
Tooth enamel is the hardest material present in mammals. Researchers used technology called mass spectrometry to scan the tooth to look for proteins, which last longer than DNA.
The fact that DNA does not survive well over time has made it difficult to bring back extinct species. Harvard University is trying to produce elephant-mammoth hybrids with DNA of animals frozen to death in the Ice Age.
Researchers hope that the breakthrough will help experts gain more understanding about how modern humans evolved.
The research was published in the journal Nature.