Comparison of two commercial methods for smooth-shelled mussels (Mytilus spp.) species identification

Seafood international trade has increased the labeling requirements in standards and regulations to include product information that enable traders and consumers to make informed choices. The European Union (EU) Regulation No. 1379/2013 imposes the declaration of an official commercial designation and scientific names for all the fishery and aquaculture products to be offered for sale to the final consumers. DNA analyses are used to enforce this regulation and to test authenticity in processed foods. We compared the performance of two mono-locus approaches for species identification (SI) in 61 Mytilus mussels: the high-resolution melting analysis of the polyphenolic adhesive protein gene and the partial sequencing of the histone H1C gene. The H1C sequences were analyzed with five different methods. Both approaches show discrepancies in the identification of putative hy-brids (0.0 < kappa < 0.687 and 0.0 < MCC < 0.724). Excluding putative hybrids, methods show substantial to perfect agreement (0.772 < kappa < 1.0 and 0.783 < MCC < 1.0). This study highlights the need to use standardized mo-lecular tools, as well as to use multi-locus methods for SI of Mytilus mussels in testing laboratories.

Automated summary

Seafood international trade has led to stricter labeling requirements, including the need for product information to help traders and consumers make informed choices. The EU Regulation imposes the declaration of official commercial and scientific names for all fishery and aquaculture products, enforced through DNA analyses. This study compares two mono-locus approaches for species identification in mussels, highlighting the need for standardized molecular tools and multi-locus methods.