PCR-SSCP method for genetic differentiation of canned abalone and commercial gastropods in the Mexican retail market

Traceability of canned abalone is not only being demanded to protect quality and certification of safety, but also to uncover black market or fraudulent practices, such as canning other gastropods sold as abalone, ‘abalone style’, or showing an abalone shell picture on the label. A forensic method for genetic differentiation of three species of abalone from other gastropods was developed with 18S rDNA analysis by PCR-SSCP. A lysin gene marker was also developed to identify abalone species in Mexico. Both markers worked correctly in raw, frozen, and canned products. In a forensic analysis, two out of seven canned brands that claimed to contain abalone contained other gastropods. None of three other brands that showed the legend ‘Abalone’ or an abalone shell picture contained abalone. The Chilean ‘loco’ Concholepas concholepas is the most common product used in abalone substitution. The lysine gene was capable of separating canned abalone based on the species. Both methods proved reliable and useful for identifying abalone and can be used to certify the authenticity of the Mexican commercial product or identify commercial fraud. By this genetic approach, the Mexican abalone industry could guarantee authenticity.