Genetic Polymorphisms Associated with Susceptibility to COVID-19
Genetic Polymorphisms Associated with Susceptibility to COVID-19
Haleh Sarrafnia,1,*Seyed Reza Mohebbi,2
1. Gastroenterology and Liver Diseases Research Center ,Shahid Beheshti University of Medical Sciences 2. Gastroenterology and Liver Diseases Research Center ,Shahid Beheshti University of Medical Sciences
Introduction: Introduction
The COVID-19 pandemic, caused by the novel SARS-CoV-2 virus, has had a serious effect on global health and economies. One interesting observation is the profoundly variable clinical outcomes in individuals infected with the virus, ranging from asymptomatic cases to severe or fatal disease [1]. Clinical outcomes are impacted by several factors, including age, gender, and comorbidities. However, growing evidence recommends that host genetic factors play a significant role in modulating the susceptibility and severity of COVID-19[2]. This article reviews some of the key genetic polymorphisms that have been associated with susceptibility to COVID-19.
Methods: Genetic Polymorphisms and Disease Susceptibility
Genetic polymorphisms allude to variation within the DNA sequence that are present in more than 1% of the population. These variations can influence an individual's susceptibility to diseases, including infectious diseases like COVID-19[3]. Several studies have been conducted to understand the relationship between genetic polymorphisms and COVID-19 susceptibility and severity. Here are some remarkable findings.
Results: ACE2 and TMPRSS2 Polymorphisms
The ACE2 gene and the TMPRSS2 gene, which encode the angiotensin-converting enzyme 2 (ACE2) and the transmembrane protease serine 2 (TMPRSS2), respectively, play critical roles in SARS-CoV-2 entry into host cells [4]. Several studies have reported that polymorphisms in these genes may influence the susceptibility to COVID-19.
A genome-wide association study (GWAS) conducted by Hou et al., recognized a few ACE2 polymorphisms related with altered ACE2 expression levels, potentially influencing the ability of SARS-CoV-2 to enter host cells [5]. So also, polymorphisms in the TMPRSS2 gene, particularly those impacting TMPRSS2 expression levels, have been associated with COVID-19 susceptibility [6].
HLA Polymorphisms
The human leukocyte antigen (HLA) system is a vital part of the immune system, liable for presenting antigens to immune cells. HLA polymorphisms can impact the immune response to infections, including SARS-CoV-2.
A study by Nguyen et al. used computational methods to predict the binding of SARS-CoV-2 peptides to different HLA alleles and found considerable variation in binding abilities, suggesting that specific HLA alleles could potentially influence COVID-19 outcomes. [7]
ABO Blood Group System
The ABO blood group system has been associated with susceptibility to various diseases, including infectious diseases. Several studies have reported an association between the ABO blood group and COVID-19. A study by Zhao et al. found that blood group A was associated with a higher risk of COVID-19, while blood group O was associated with a lower risk. [8]
Other Genetic Factors
Several GWAS studies have identified other genetic loci associated with COVID-19 susceptibility and severity. A study by the Severe Covid-19 GWAS Group identified a gene cluster on chromosome 3 as a genetic susceptibility locus in patients with COVID-19 with respiratory failure [9]. Another GWAS by Pairo-Castineira et al. identified additional loci associated with COVID-19 severity, including genes involved in antiviral immunity and lung inflammation. [10]
Conclusion: Conclusion
Whereas the identification of genetic polymorphisms related with COVID-19 susceptibility and severity
provides profitable bits of knowledge, it's critical to note that these discoveries are preparatory and
require further validation. In addition, genetic factors are just one piece of the puzzle, and other factors,
such as age, gender, comorbidities, and environmental factors, also play remarkable roles in modulating
COVID-19 outcomes. Nevertheless, understanding the genetic basis of COVID-19 susceptibility could
potentially aid in the development of personalized risk evaluations and therapeutic procedures.