DNA barcoding and mini-barcoding involve Cytochrome Oxidase Subunit I (COI) gene in mitochondrial genome and are used for accurate identification of species and biodiversity. The basic goal of the current study is to develop a complete reference database of fishes. It also evaluates the applicability of COI gene to identify fish at the species level with other aspects i.e., as Kimura 2 parameter (K2P) distance. The mean observed length of the sequence was ranging from 500 to 700 base pairs for fish species in DNA barcoding and from 80 to 650 base pairs for DNA mini-barcoding. This method describes the status of known to unknown samples but it also facilitates the detection of previously un-sampled species at distinct level. So, mini-barcoding is a method which focuses on the analysis of short-length DNA markers and has been demonstrated to be effective for species identification of processed food containing degraded DNA. While DNA metabarcoding refers to the automated identification of multiple species from a single bulk sample. They may contain entire organisms or a single environmental sample containing degraded DNA. Despite DNA barcoding, mini-barcoding and metabarcoding are efficient methods for species identification which are helpful in conservation and proper management of biodiversity. It aids researchers to take an account of genetic as well as evolutionary relationships by collecting their morphological, distributional and molecular data. Overall, this paper discusses DNA barcoding technology and how it has been used to various fish species, as well as its universality, adaptability, and novel approach to DNA-based species identification.
