Primary hypertension is also known as prime or essential hypertension. It is characterized by elevated systolic blood pressure (SBP) of 140 mmHg or higher and diastolic blood pressure (DBP) of 90 mmHg or higher (James et al., 2014; L. Ji et al., 2020; Kearney et al., 2005) that persist over time and can lead to serious health consequences such as stroke, heart disease, and kidney failure (de Freitas Gonçalves et al., 2022; James et al., 2014). Primary hypertension is a prevalent, multifactorial, and complex condition affecting millions worldwide (Arnett and Claas, 2018; Mills et al., 2020; Tanira and Al Balushi, 2005). By 2040, approximately 1.6 billion (20.3% of the world's population) people are expected to have hypertension, leading to half of all deaths due to cardiovascular diseases worldwide (Boateng and Ampofo, 2023; Forouzanfar et al., 2017).

The etiology of primary hypertension is complex and not fully understood. It is supposed to be caused by the complex interaction between environment and genetic factors (L. Ji et al., 2020; Singh et al., 2016; Tanira and Al Balushi, 2005; Thomas, 2010) (Fig. 1). Genetic analyses have shown that hypertension is a polygenic disease, with multiple genetic variants contributing to its development (Davidov et al., 2022; Pratamawati et al., 2023). These genetic factors are estimated to be involved in approximately 30–50% of blood pressure variation (de Freitas Gonçalves et al., 2022; Patel et al., 2017; G. Wilk and Braun, 2018) Environmental factors, such as diet, obesity, stress, and lack of exercise, also play a role in the development of hypertension (Azam and Azizan, 2018; Brookes, 1999; Waken et al., 2017).

Amongst various types of genetic variation, the role of single nucleotide polymorphisms (SNPs) in primary hypertension has been investigated in several studies. (Lifton et al., 2001a; Mbaabu et al., 2023). SNPs are commonly found across the entire human genome, appearing at an approximate frequency of one occurrence per every 1000 nucleotides. There can be millions of SNPs in a genome, making them an important target for genetic research (Brookes, 1999; Shastry, 2009). Advancements in genotyping technology have enabled the application of genome-wide association studies (GWAS) to detect SNPs associated with different diseases, including primary hypertension (Azam and Azizan, 2018; Lifton et al., 2001b).

SNPs have been shown to regulate gene expression and can affect the stability and activity of the expressed protein/enzyme (Overway et al., 2022; G. Wilk and Braun, 2018). Detection of SNPs is of great value in precision medicine as they can help determine an individual's susceptibility to different diseases and drug reactions (Arafah et al., 2021) SNPs can be used as genetic markers to understand the effects of inherited single-gene variations on drug mobilization and action (Fekadu and Tileye, 2022). Additionally, SNPs can be used to develop PCR-based testing methodologies for the detection and confirmation of risk alleles in specific populations (L. Zhang et al., 2022a; Zhang et al., 2022b). SNPs in genes involved in blood volume regulation, vascular contractility, and vasculature impact the risk of developing essential hypertension (Neto et al., 2021; Shahid et al., 2022; Timasheva et al., 2017a, 2017b). In hypertension, SNPs contribute to substantial susceptibility when combined with environmental factors (Fu et al., 2018a, 2018b; Heydarpour et al., 2023a, 2023b). Overall, SNPs play a crucial role in understanding genetic mechanisms for disease development and progression and can have significant implications in clinical practice.

This review article presents an overview of the current literature on SNP-based biomarkers in primary hypertension, focusing on three primary factors: blood volume and salt regulation imbalance, enhanced peripheral vascular contractility, and blood vessel wall deformity. It also discusses future directions in SNP research and how these investigations can potentially revolutionize our comprehension of the genetic basis linked to the condition. This includes the exploration of various genes and pathways associated with primary hypertension.