Current Status of Sargassum DNA Barcoding over the Last Three Decades from 1995-2025

Abstract

Sargassum (Phaeophyceae) is a cosmopolitan macroalgae with great industrial and economic potential. Despite this, identification of Sargassum species with traditional taxonomy – morphological traits, often led to ambiguity since it is known that Sargassum has high phenotypic plasticity. Modern identification of Sargassum, DNA barcoding, is relatively new compared to the traditional means. This systematic review (1995-2025) aimed to provide an updated overview of the current climate of Sargassum DNA barcoding globally. The literature determination of this systematic review followed PRISMA framework, which started from literature search procured from major databases, Scopus, ResearchGate (RG), and Google Scholar (GS). After going through the criteria for duplicate, title-abstract, and full-text screening, 89 studies that were included for extraction and analysis. This review revealed that Sargassum DNA barcoding studies have been done with 38 different genetic markers from the nuclear, chloroplast, and mitochondria gene which are used 90, 47, and 83 times respectively. The most frequently used marker is the nuclear ribosomal marker, ITS2, which had been used 41 times across 89 studies. Sargassum DNA barcoding studies have also been done on 109 out of 356 taxonomically accepted Sargassum species, forms, and varieties, in 55 different locations around the world. This review provides an up-to-date and comprehensive overview of the global status of DNA barcoding studies on Sargassum as well as identifies knowledge gaps and areas for further research, which can expand the DNA sequence database of Sargassum and shed light on the taxonomic status of Sargassum species.