Functional Characterization of Non-Synonymous SNPs in the Hypertension-Associated AGT Gene Using Bioinformatic Tools
DOI:
https://doi.org/10.61919/4jj1yk96Keywords:
AGT, angiotensinogen, hypertension, nsSNP, RAAS, bioinformatics, protein stability, MutPred, I-TASSERAbstract
Background: Hypertension, the “silent killer,” is a multifactorial disorder driven by genetic and environmental factors. Approximately 90% of cases are essential hypertension. Despite effective pharmacotherapy, there is no permanent cure; lifestyle modification remains foundational. Within the renin–angiotensin–aldosterone system (RAAS), the angiotensinogen (AGT) gene has been widely investigated and linked to essential hypertension across populations. Objective: To identify potentially pathogenic non-synonymous variants (nsSNPs) in AGT and evaluate their effects on protein structure, stability, and function using comprehensive in-silico analyses. Methods: Functional impact was predicted with SIFT, PolyPhen-2, PhD-SNP, SNP&GO, and PANTHER. Protein stability was assessed with I-Mutant 3.0 and MUpro. Evolutionary conservation was analyzed using ConSurf; functional consequences were explored with MutPred2. Post-translational modifications (PTMs) were screened. Three-dimensional structures were modeled with I-TASSER; wild-type vs mutant conformations were examined in Chimera 1.11 and compared using TM-align. Gene–gene and protein–protein interaction networks were explored using GeneMANIA and STRING, respectively. Results: Among 475 missense variants retrieved, 21 nsSNPs were consistently predicted as deleterious by all five functional tools. Most of these variants decreased predicted protein stability (I-Mutant: 18/21; MUpro: 20/21). Several mapped to highly conserved and functionally exposed positions. Structural modeling indicated measurable deviations between wild-type and mutant models (TM-scores ~0.97–0.99; RMSD ~0.87–1.76 Å). Network analyses highlighted the centrality of AGT within RAAS-related interactions. Conclusion: The study prioritizes 21 AGT nsSNPs with strong in-silico evidence for structural/functional impact. These candidates merit targeted association studies and experimental validation to clarify their roles in hypertension pathophysiology and to inform precision therapeutics.
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Copyright (c) 2025 Huma Israr, Aina Sibghat, Fajar Baig, Wagma Gul, Fazal Jalil, Naveed Khan (Author)
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