Molecular Characterisation of Parvalbumin Gene: Evolutionary Insights and Forensic Applications for Fish Species Identification and Authentication

Abstract

Abstract Parvalbumin (pvalb), a low molecular weight calcium-binding protein, plays a crucial role in regulating Ca2+ switching in fast-twitch muscle fibres and has been identified as a major cause of fish-induced food allergies. The molecular evolution of pvalb genes in teleost fish and its cause, duplication of the whole genome, was investigated, revealing high diversity and complex gene repertoires, making detection and identification challenging. This study provides robust genomic evidence of the complex evolution of parvalbumin genes in teleost fish. In addition to its role as a potent allergen, the pvalb gene, a nuclear gene, can serve as a valuable molecular marker. Keeping this in mind, a real-time PCR assay is developed to detect and quantify two European anglerfish species simultaneously, Lophius piscatorius and Lophius budegassa, which are susceptible to illegal species substitutions in the global seafood trade. The assay targets the intronic region of the pvalb gene, demonstrating high specificity, efficiency, and robustness, making it a potential forensic tool to prevent food fraud and ensure the accurate identification of fish species. Furthermore, a standardised quantitative PCR-based method is presented for the β-pvalb gene in Lophius piscatorius, utilising a plasmid DNA calibrator...