Designing Primers for Amplification of Coi, Cyt-B, Nd2 and Fib7 in Swiftlet (Aerodramus spp.)

Edible bird’s nests (EBN) are highly nutritious and valued food for their numerous health benefits. Consequently, their high economic value and increasing global consumption demand for EBN have contributed to a rise in counterfeited food issue. Currently, the common method for identifying the origin of edible bird nests is the DNA barcoding PCR-based technique because of the limitations of morphological identification methods; however, the primers currently used for PCR face specific challenges in amplifying DNA from edible bird nests. Thus, newly designed primers are necessary.

This study aims to redesign primers from the DNA barcode sequences of the mitochondrial genes cytochrome-c oxidase subunit I (COI), NADH dehydrogenase subunit II (ND2), cytochrome b (Cyt-b) and the nuclear gene β-fibrinogen intron 7 (Fib7) of Swiftlet belonging to the Aerodramus genus.

Four primer pairs AeroCOIf/AeroCOIr, AeroND2f/AeroND2r, AeroCytbf/AeroCytbr Cyt-b gene and AeroFib7f/AeroFib7r were designed successfully amplifying DNA from Aerodramus spp. The resulting amplicon sizes were 157 bp for COI, 150 bp for ND2, 130 bp for Cyt-b and 173 bp for Fib7 with the optimal annealing temperature of 60^οC. For the result of the primers sensitivity investigation, the AeroCOIf/AeroCOIr, AeroND2f/AeroND2r, AeroCytbf/AeroCytbr and AeroFib7f/AeroFib7r primers was able to detect DNA concentration at 15×10^-4 ng/µL, 15 ng/µL, 15×10^-3 ng/µL and 15 ng/µL, respectively. These results demonstrate that these new primers could effectively amplify DNA from EBN belonging to Aerodramus spp.