Wildlife Forensics Using SNP Panels

Abstract

Wildlife crime -- including illegal trade, poaching, and fraudulent labelling of animal products -- represents the fourth-largest criminal enterprise globally, generating an estimated USD 23 billion annually and threatening hundreds of species protected under CITES. Effective prosecution of wildlife crime requires forensic identification tools capable of determining species identity, geographic population of origin, and individual identity from degraded biological trace evidence including hair, feathers, bone, processed ivory, dried meat, and preserved fins. Single nucleotide polymorphism (SNP) panels offer compelling advantages over traditional microsatellite and mitochondrial DNA approaches for wildlife forensics: SNPs amplify reliably from degraded DNA, are amenable to high-throughput massively parallel sequencing, and can simultaneously address species, population, and individual identity questions from a single analytical workflow. This study developed and validated forensic SNP panels for twelve high-priority CITES-listed species -- spanning African and Asian elephants, rhinoceroses, big cats, great apes, sharks, and sea turtles -- using population genomic reference datasets comprising 2,847 individuals from 94 geographic populations. Species identification panels (24-48 SNPs) achieved 100% species assignment accuracy across all 12 focal taxa in blind validation tests using 487 forensic-grade samples. Geographic origin assignment panels (96-192 SNPs) correctly assigned population of origin with >= 92.4% accuracy for all species, matching verified provenance for 98.7% of samples within the correct country. Individual identity panels (48-96 SNPs) produced match probabilities (PM) below 1 x 10-12 for all species, exceeding accepted forensic standards. These validated panels are being implemented in INTERPOL and UNODC wildlife crime forensic laboratories across 18 countries.