paleogenomics

Paleogenomics is a field of science based on the reconstruction and analysis of genomic information in extinct species. Improved methods for the extraction of ancient DNA (aDNA) from museum artifacts, ice cores, archeological or paleontological sites, and next-generation sequencing technologies have spurred this field. It is now possible to detect genetic drift, ancient population migration and interrelationships, the evolutionary history of extinct plant, animal and Homo species, and identification of phenotypic features across geographic regions. Scientists can also use paleogenomics to compare ancient ancestors against modern-day humans. The rising importance of paleogenomics is evident from the fact that the 2022 Nobel Prize in physiology or medicine was awarded to a Swedish geneticist Svante Pääbo [1955-], who worked on paleogenomics.

== Background == Initially, aDNA sequencing involved cloning small fragments into bacteria, which proceeded with low efficiency due to the oxidative damage the aDNA suffered over millennia. aDNA is difficult to analyze due to facile degradation by nucleases; specific environments and postmortem conditions improved isolation and analysis. Extraction and contamination protocols were necessary for reliable analyses. With the development of the Polymerase Chain Reaction (PCR) in 1983, scientists could study DNA samples up to approximately 100,000 years old, a limitation of the relatively short isolated fragments. Through advances in isolation, amplification, sequencing, and data reconstruction, older and older samples have become analyzable. Over the past 30 years, high copy number mitochondrial DNA was able to answer many questions; the advent of NGS techniques prompted far more. Moreover, this technological revolution allowed the transition from paleogenetics to paleogenomics.