DNA Barcoding
Identify species quickly and accurately using unique genetic “barcodes.”
Highlights:
DNA barcoding is a method used to identify species by analysing a short, standardized DNA sequence from a specific gene. Think of it as a genetic "fingerprint" for a species. Much like a supermarket scanner reads a product's barcode to retrieve its identity from a database, a DNA sequencer reads an organism's unique DNA barcode to identify the species from a vast reference library. The concept relies on the "barcoding gap," where genetic variation is minimal within a species but significant between different species. This makes the chosen DNA region an effective identifier.
The process of DNA barcoding involves several key steps that can be performed with a sample of tissue, hair, or even environmental DNA (eDNA), Sample collection from environmental sources like water or soil. DNA extraction: DNA is extracted and purified from the tissue sample in a lab. DNA amplification (PCR): A specific gene region is copied millions of times using a technique called Polymerase Chain Reaction (PCR). This creates enough of the target DNA to be analyzed. The specific genes used for barcoding vary by kingdom:Animals: The standard barcode is a region of the mitochondrial gene Cytochrome C Oxidase I (COI) for Plants, the most common barcodes are the rbcL and matK genes from the chloroplast genome. Fungi, the Internal Transcribed Spacer (ITS) region is typically used. DNA sequencing amplified DNA is sequenced to determine the exact order of the nucleotide bases (A, T, C, G) that make up the barcode.