Leather Species Identification via Mitochondrial DNA Polymerase chain Reaction

Abstract

Currently the identification of leather species is mainly via a skilled operator using optical microscopy and an extensive visual reference library. However, due to the limitations of optical microscopy and in cases where the leather surface is heavily corrected or finished, it is not always possible to accurately determine the leather species. Therefore, it is crucialto develop a reliable and easy to perform approach to overcome these limitations. In this paper, we used the unique DNA sequence present in every species to identify leather. The conversion process of making leather destroys much of the DNA present but the high copy number of mitochondrial DNA (mtDNA) in relation to nuclear DNA makes some mtDNA likely to survive and be detected via polymerase chain reaction (PCR). However, leather DNA is highly degraded and inhibitors present in the extracted DNA make successful PCR challenging. There are only a few related works reported in the literature attempting to use DNA for leather species identification and they provide limited technical details. In this study, species-specific primers for PCR were designed, conditions for DNA extraction from leather followed by PCR were optimized, and a detailed protocol was also provided. As a proof of concept, our approach demonstrated that the species of leather can be reliably detected via PCR targeting mtDNA.