Molecular Identification of Polychaetes Based on 18s rRNA Gene 103 7. MOLECULAR IDENTIFICATION OF POLYCHAETES BASED ON 18S rRNA GENE

Molecular tools have revolutionized the exploration of biodiversity, especially in organisms for which traditional taxonomy is difficult (Tang et al., 2012). The small subunit (SSU) 18S rRNA gene is one of the most frequently used genes in phylogenetic studies and an important marker for random target PCR in environmental biodiversity screening. 18S rDNA is a nuclear ribosomal gene, commonly referred to as the nuclear small ribosomal subunit (SSU), ~1800-2000 nucleotides in length. This gene is part of a tandem repeated element in the nuclear genome that also includes the 28S, 5.8S, and the internal transcribed spacer regions (ITS) (Hillis and Dixon, 1991).