Single Nucleotide Polymorphisms in HIF-1A, VEGFa, and VHL Genes: A Comparative Study between Sea Level and High-Altitude Residents in West Saudi Arabia

Siraj B. Alharthi, Ijtihed Kilani, Abdullah Alsoliman, Romar P. Pascual, Mohamed H. Zainy, Ahmed S Albariqi, Yahya Alzahrani, Ahmed Alshehri, Ahmed El-Shehawi, Hashem Borayk, Mohamed Morsi M. Ahmed

Abstract


Background: This comprehensive molecular study investigates the genetic variations in individuals residing at different altitudes in West Saudi Arabia, specifically contrasting sea-level residents in Jeddah (SL) with high-altitude dwellers in Taif (HA). The study focuses on the significant role of genetic adaptations in response to environmental challenges, particularly hypoxia. Understanding these genetic differences according to geographical location is crucial for multiple reasons. It not only sheds light on the adaptive mechanisms that humans develop in response to environmental stressors like reduced oxygen levels but also has broader implications for medical, anthropological, and evolutionary studies. By exploring how distinct populations adapt to their environments, this research provides valuable insights into the complex interplay between genetics, health, and disease, highlighting the importance of considering genetic diversity in medical and genetic research.

Methods: The research involved amplifying and sequencing three pivotal genes associated with hypoxia adaptation: Hif-1a, VEGFa, and VHL. Advanced genomic techniques were utilized to analyze samples from 22 volunteers, 10 from the sea level region of Jeddah and 12 from the high-altitude region of Taif. The study aimed to identify and analyze single nucleotide polymorphisms (SNPs) in these genes and their implications in altitude adaptation.

Results: Distinct SNPs were identified in the Hif-1a, VEGFa, and VHL genes, with high-altitude residents displaying more pronounced variations. The phylogenetic analysis demonstrated clear genetic clustering based on altitude, highlighting the molecular adaptations induced by altitude variations. The study reveals a complex interplay between genetics and environmental conditions, significantly contributing to our understanding of human adaptation to high altitudes.

Conclusion: This research underscores the profound impact of altitude on human genetics. The findings provide critical insights into how genetic variations facilitate adaptation to challenging environmental conditions, such as hypoxia, encountered at high altitudes. These insights have broad implications, potentially informing medical research related to altitude sickness and other altitude-related health issues.

Keywords: High-Altitude Adaptation; Single Nucleotide Polymorphisms (SNPs); Hif-1a Gene; VEGFa Gene; VHL Gene; Phylogenetic Analysis; Saudi Arabian Populations  


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