Crossing the pond: genetic assignment detects lobster hybridisation

Area of Science:

• Marine Biology
• Genetics
• Conservation Science

Background:

• Introduced American lobsters (Homarus americanus) in Europe pose risks to native European lobsters (H. gammarus) through hybridization.
• Morphological identification methods are insufficient to detect hybrids, necessitating molecular approaches.

Purpose of the Study:

• To develop and validate molecular tools for distinguishing American lobsters, European lobsters, and their hybrids.
• To assess the utility of single nucleotide polymorphisms (SNPs) for identifying cryptic hybridization in wild lobster populations.

Main Methods:

• Genotyping of 1,308 European lobsters, 38 American lobsters, and 30 hybrid offspring using 79 single nucleotide polymorphisms (SNPs).
• Development of a core panel of 12 SNPs for efficient species and hybrid identification, even in cooked samples.

Main Results:

• A panel of 79 SNPs effectively assigns species in Homarus, enabling robust identification of American and hybrid individuals in European waters.
• A subset of 12 SNPs can accurately differentiate pure species and detect the American genetic component in hybrids.

Conclusions:

• Developed SNP loci provide unambiguous identification of hybrid lobsters, overcoming limitations of traditional morphology.
• These molecular tools are crucial for investigating the prevalence of cryptic hybridization and evaluating alien gene introgression into native European lobster populations.