Illegal wildlife trade is currently on the rise, and it is becoming one of the most lucrative crime sectors. The rarer the species, the higher the demand. Wildlife trade falls under international regulations, such as the CITES convention. Proving that this convention has been violated is a complex process and can be very difficult to do. DNA analysis methods remain (in many cases) the only way to determine whether a certain specimen originated from a protected animal species, a specific individual, or a species in which it is legal to trade. Tanned animal hides are a specific type of specimen. With this type of biological material, obtaining amplifiable DNA is often difficult. This pilot study aimed to map the effect of the chemicals used in the tanning process on the degradation of the DNA yielded from such samples. The DNA was quantified using two different approaches: qPCR and Qubit fluorometry. The degree of DNA fragmentation was assessed by determining the degradation index. The results indicate that reagents containing chromium have the greatest influence on DNA degradation. However, by using the presented protocol, enough amplifiable DNA can be obtained from hides treated with aluminum-based reagents.

2nd Faculty of Medicine Charles University 5 Úvalu 84 150 00 Prague Czech Republic

Bulovka University Hospital Budínova 2 180 81 Prague Czech Republic

CRL Radiocarbon Laboratory Department of Radiation Dosimetry Nuclear Physic Institute of the Czech Academy of Sciences Na Truhlářce 38 180 86 Prague Czech Republic

Faculty of Forestry and Wood Sciences Czech University of Life Sciences Kamýcká 129 165 00 Prague Czech Republic

Forensic DNA Service Budínova 2 180 81 Prague Czech Republic

Institute for Environmental Sciences Charles University Benátská 2 128 00 Prague Czech Republic

Institute of Geochemistry Mineralogy and Mineral Resources Faculty of Science Charles University Albertov 6 128 00 Prague Czech Republic

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