Genetic characterization of honey bee populations, particularly the identification of Africanized honey bees, has traditionally been based on different molecular methods that involve the amplification and analysis of different regions of the mitochondrial or nuclear genome which often take a long time. We introduce high-resolution melting analysis (HRM) as a novel approach for rapid and cost-effective identification of the African lineage in Apis mellifera populations from mitochondrial DNA extracted from honey. Samples were collected from 111 apiaries in 13 Argentinean provinces between 2012 and 2018. Total DNA was extracted from 10 g honey sediment and subjected to quantitative PCR (qPCR) using specific primers (APIS-F/Afr207R) amplifying a 207 bp product. Positive controls (Africanized/Non-Africanized) were used for mitotype validation and a subset of qPCR products were sequenced to compare different haplotypes. HRM analysis enabled the quick detection of sequence polymorphisms in short amplicons generated by qPCR. Among the analyzed apiaries, 26 located above 35° S in Misiones, La Rioja, Catamarca, Formosa, Corrientes, Córdoba, and Santa Fé exhibited the Africanized mitotypes while the remaining apiaries below this latitude, mainly in Buenos Aires, Rio Negro, Neuquén, and Entre Ríos, showed the European mitotypes. These results align with previous characterizations in the region. HRM analysis demonstrated high sensitivity and effectiveness, requiring minimal DNA input, and reducing costs and sampling efforts. This approach provides a rapid and reliable method for identifying the African lineage, facilitating honey bee breeding programs, conservation efforts, and management strategies in regions with Africanized honey bee populations.
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