Everyone remembers March 11th, 2020, as the day the world shutdown. Professional and collegiate sports canceled, flights and travel banned, the economy tanking, rumors of lockdowns, quarantines, and online school force school boards and government officials to make tough decisions instantaneously to prevent the spread, the spread of “severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)”, also, more commonly known as Covid-19. Words and phrases like “6 feet apart”,“high-risk”, “social distancing”,“asymptomatic”, “flatten the curve”, “stimulus checks”, “covid testing”, “contact tracing and exposure” and “wear a mask” became part of our vocabulary. Today, the death toll rises to 2.41 million people worldwide and almost 500,000 American deaths. After approximately 109 million cases world wide, the percentage of dying due to Covid-19 is 3%. While this number is still too high, and I feel sympathetic for all those impacted due to Covid-19, those numbers had me curious as to what makes a person more at risk than another. Through lots of scientific research and study, biologists and geneticists have determined that there are direct linkages to genetics and the inherited risks of Covid-19, like pre-existing conditions that a person may already deal with, increasing disease progression and spread in the body, and genetic variants are identified to significantly increase risk of COVID-19 mortality among the patients.
Covid-19 has been proven to spread rapidly, both in infection rates among a population and in the body. The virus mainly spreads when respiratory droplets from infected people land in the mouths or noses of others or possibly when inhaled into the lungs by others. This is why, during lockdowns and quarantines, people have been urged, and in some cities, like Kansas City, required by law to wear a mask and have business follow proper Covid-19 safety protocols. Before all the shutdowns, when life was normal, mass gatherings and constant interactions between people was the reason for the initial outbreak. Yet, our genetics have proven to be a key factor in how the virus spreads in our body, and our response to it. A recent genetic association study identified a gene cluster on chromosome 3 as a risk locus for respiratory failure after infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). One region on chromosome 3, which contains six genes, and one region on chromosome 9, that determines ABO blood groups, and have been found to be connected. The genetic variants that are most associated with severe COVID-19 on chromosome 3 are all in high linkage disequilibrium, meaning they are all strongly associated with each other in the population. These connections are also found in various groups of people in vast parts of the world. A study was done comprising 3,199 hospitalized patients with coronavirus disease 2019 (COVID-19) and control individuals showed that this cluster is the major genetic risk factor for severe symptoms after SARS-CoV-2 infection and hospitalization. In that study, they found that these Covid-19 recessing genes are inherited from Neanderthals and are carried by around 50% of people in south Asia and around 16% of people in Europe, showing how the spread of the virus, and the connection of genetics, lead to a faster, and more wild, outbreak for infection rates globally, and a rate of spreading in our body.
Genetic variants have been researched and proven to increase the Covid-19 mortality rate. Genetic variation is the difference in DNA among individuals or the differences between populations. There are multiple sources of genetic variation, including mutation and genetic recombination. There was a study conducted researching different genes from people who share similar genetics and heritage, and the target for the study was people, both males and females, with white British history. Through sample processing and genotype quality control, many experiments were run and lots of data was collected, and then analyzed. The researchers found that there were 8 super-variants that are consistently identified across multiple replications as susceptibility loci for COVID-19 mortality. The identified risk factors on Chromosomes 2, 6, 7, 8, 10, 16, and 17 contain genetic variants and genes related to cilia dysfunctions (DNAH7 and CLUAP1), cardiovascular diseases (DES and SPEG), thromboembolic disease (STXBP5), mitochondrial dysfunctions (TOMM7), and innate immune system (WSB1). It is noteworthy that DNAH7 has been reported recently as the most down-regulated gene after infecting human bronchial epithelial cells with Covid-19. These variations are scientific clues for the better understanding of how the virus, and can be useful in the future when determining how viral infections impact similar people, genetically speaking, and shows the dangers about what can happen during genetic variation on certain chromosomes.
In conclusion, biologist and geneticist, backed by scientific research, have proven that genetics play a very important role in determining the risk when becoming infected with Covid-19, by demonstrating that people with pre-existing conditions, like diabetes, may be more inclined to suffer from Covid-19, and that increase disease spread, both globally transmitted person to person and in our body, along with genetic variation that may occur on certain chromosomes may also lead to a higher chance of dying due to Covid-19. Now, almost a year later than March 11th, 2020, vaccinations for Covid-19 are being disrupted and given every day, and the light at the end of the tunnel just keeps getting brighter and brighter, as we all hope soon that this pandemic is well behind us. However, until then, as individuals in our society, we all need to do our part to keep ourselves, our families, and most importantly, each other safe. Today, all we see on people is the mask on our faces, and we don’t, can’t, and never will see the underlying health conditions, or the genetic variation on someones chromosomes, that may prove to be a severe, even deadly, case of Covid-19. So, lastly, please continue to be safe, and follow all Covid-19 safety protocols, because you never know how severe someone may truly suffer if infected with Covid-19, because that is truly, only based on their genetics.