Ancient DNA: extraction, characterization, molecular cloning, and enzymatic amplification.

TLDR

The study aims to use PCR to amplify and analyze short mitochondrial DNA sequences from ancient remains for anthropological and evolutionary insights. The authors examined chemical and enzymatic properties of DNA extracted from dry tissues aged 4–13,000 years across four species, including extinct marsupial wolf and giant ground sloth, and employed PCR to amplify short mitochondrial fragments. The ancient DNA was consistently low‑molecular‑weight and oxidatively damaged, making cloning difficult, but PCR amplification enables diachronical evolutionary studies.

Abstract

Several chemical and enzymatic properties were examined in the DNA extracted from dry remains of soft tissues that vary in age from 4 to 13,000 years and represent four species, including two extinct animals (the marsupial wolf and giant ground sloth). The DNA obtained was invariably of a low average molecular size and damaged by oxidative processes, which primarily manifest themselves as modifications of pyrimidines and sugar residues as well as baseless sites and intermolecular cross-links. This renders molecular cloning difficult. However, the polymerase chain reaction can be used to amplify and study short mitochondrial DNA sequences that are of anthropological and evolutionary significance. This opens up the prospect of performing diachronical studies of molecular evolutionary genetics.