Computational Identification And Distribution Of Mirror Repeats In Transcripts Of Human PAH Gene

Laxita Singh¹, Namrata Dangi^2*

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ABSTRACT

Repetitive DNA elements contribute significantly to genome organization and structural complexity. Among these, mirror repeats represent a distinct class of symmetric sequences capable of forming noncanonical DNA structures, yet their distribution in clinically important human genes remains poorly characterized. In this study, we performed a comprehensive computational analysis to identify and map mirror repeats within human phenylalanine hydroxylase (PAH) gene transcripts. Transcript sequences were retrieved and analyzed using a BLAST-based Fast Pairwise Complementary BLAST (FPCB) approach to enable sensitive detection of symmetric DNA motifs. Mirror repeats were systematically identified, classified as perfect or imperfect, and mapped across the coding sequence and exon regions. Fragment-wise analysis of the PAH coding sequence identified a total of 86 mirror repeats, while exon-wise curation of the canonical transcript revealed 63 unique mirror repeats localized within coding exons. The detected mirror repeats exhibited a non-uniform distribution across coding fragments and exons. This study provides the first detailed descriptive catalog of mirror repeats in PAH gene transcripts and establishes a reproducible computational framework that can serve as a reference for future studies of symmetric DNA motifs.

Keywords: Mirror repeats, Symmetric DNA sequences, Phenylalanine hydroxylase (PAH) gene, PAH transcript variants, Coding sequence analysis, Exon-wise repeat distribution, Fast Pairwise Complementary BLAST (FPCB), Repetitive DNA elements, Computational genomics, In silico sequence analysis.

How to cite this article: Singh L, Dangi N. Computational Identification And Distribution Of Mirror Repeats In Transcripts Of Human PAH Gene. Int J Drug Deliv Technol. 2026;16(15s): 375-383. DOI: 10.25258/ijddt.16.15s.44

Source of support: Nil.

Conflict of interest: None