Metabarkoding

Metabarkoding is a method used in molecular biology to identify and quantify species within a sample by sequencing a specific DNA barcode region that is common to many organisms but varies between species. This technique is particularly useful for analyzing complex mixtures of DNA, such as those found in environmental samples, gut contents, or stool. Unlike traditional barcoding that focuses on individual organisms, metabarkoding analyzes DNA from multiple individuals or species simultaneously, providing a broader picture of biodiversity.

The process typically involves extracting DNA from a mixed sample, amplifying a target barcode gene (like the 16S rRNA gene for bacteria, or the COI gene for eukaryotes) using PCR, and then sequencing the amplified fragments. The resulting sequence data is then compared against reference databases containing known DNA barcodes. By analyzing the abundance of different barcode sequences, researchers can infer the species composition and relative proportions within the original sample.

Metabarkoding has revolutionized ecological studies, allowing for rapid and cost-effective assessment of biodiversity in various environments. It is employed in fields such as ecology, conservation biology, environmental monitoring, and even forensic science. The accuracy and effectiveness of metabarkoding depend heavily on the quality of the DNA extraction, the choice of barcode marker, and the comprehensiveness of the reference databases used for taxonomic identification. Challenges include potential biases in DNA amplification and the presence of non-target DNA.