Molecular Characterization and Phylogenetic Analysis of the ITS2 Gene of Enterobius vermicularis Isolates

Background and Aim: Enterobius vermicularis (E. vermicularis) is a parasitic nematode infecting humans, mainly children, with a prevalence rate above 35% in some countries. Its molecular studies are still scant. Precise diagnosis and understanding of genetic variation are essential in managing enterobiasis. This study used DNA sequencing and phylogenetic analysis to detect E. vermicularis by genetic variation in the internal transcribed spacer 2 (ITS2) gene. Materials and Methods: Stool samples were collected randomly from 56 infected patients and 60 healthy individuals as the control group. Genomic DNA was isolated, and PCR was done using primers against ITS2 region of rDNA. Our research was conducted with the utmost thoroughness, as evidenced by DNA sequencing determining the genetic associations and variations of rDNA (ITS2) among E. vermicularis isolates. The sequences were then compared with NCBI-BLAST sequences for the genetic homology and variation analysis, ensuring the accuracy and reliability of the results. Results: In the molecular testing, 32 of the 56 samples were positive for the ITS2 gene of E. vermicularis. The percentage identity of local E. vermicularis IQN.1-10 isolates with those available in the NCBI-BLAST database homology ranged from 99.54% to 99.56%. The genetic variation analysis revealed three deletions and substitution mutations, with a total variation percentage of 0.44% to 0.46%. These findings not only provide a deeper understanding of E. vermicularis but also hold promise for the development of more effective strategies for managing enterobiasis, giving hope for the future. Conclusion: The results indicated high accuracy of the molecular diagnosis and the importance of ITS2 as the most important genetic marker due to its highly conserved nature. These new data on E. vermicularis genotypes from Iraq reflect the diversity and thus warrant further molecular studies across Iraq to effectively consider the genetic landscape and help in diagnostic and control measures.