Forensic botany: potential usefulness of microsatellite-based genotyping of Croatian olive (Olea europaea L.) in forensic casework

Abstract

Aim: To assess genotyping with microsatellite-based markers of the olive (Olea europaea L.) for potential application of olive as legal case evidence, with regard to the degree of variability within the Croatian olive genomic pool and to the effectiveness of the chosen set of microsatellite-based markers in revealing olive divergence.

Methods: The total of 44 autochthonous Croatian olive specimens were subjected to genotyping with 16 previously described and developed microsatellite-based markers. According to previous morphological analyses, 44 specimens were classified into 30 cultivars with the exception of an additional, previously unassigned specimen.

Results: Genotyping of 44 specimens distinguished a total of 44 different genotype profiles by 16 microsatellite-based loci. Average expected heterozigosity amounted to 0.758, which points to significant diversity of Croatian olives.

Conclusion: Croatian olive genotyping showed strong varietal discrimination up to the single tree and considerable potential application of olive as evidence in investigation of crime, accident, and suicide circumstances.

Figure 1

Analyzed olive specimens and native areas of their cultivation. The oval indicates geographical location of olive specimens in Croatia, sampled in this study.

Figure 2

The electropherogram of olive DNA obtained in this study by applying UDO99-024 microsatellite-based marker (internal size standard – LIZ 500). X-axis indicates fragment lenght (bp), while Y-axis indicates relative flourescent units (RFU) that are proportional to the amount of PCR product.