COVID-19 Risk Predicted by Blood Type

Your blood type might put you at greater risk for COVID-19, according to a paper published this month in the Blood Advances by researchers from Harvard. Inspired by recent genome-wide association studies which found the locus responsible for blood type expression to be among the most significant genetic predictors of SARS-COV-2 infection, they found that SARS-COV-2, the coronavirus responsible for COVID-19 preferentially binds blood group A, likely making people with this blood type more susceptible to infection.

There are several blood groups found in humans. The basic blood groups are denoted ABO(H) for the carbohydrate chains A, B, AB, and O, with H representing the “Bombay phenotype” which can be present or absent. In addition there is the rhesus factor, which plays a role in blood transfusion compatibility and can be negative (-) or positive (+), making one either A-, A+, B-, B+, and so on.

I tested my blood type with these cards in a fun lab activity after donating blood for a study

The reason why your blood type might influence your risk for infection by the virus is because, the receptor-binding domain of SARS-COV-2 shares genomic sequence similarity with an ancient lectin family called galectins that are known to bind blood group antigens.

Galectins are proteins that bind carbohydrates (string of sugars) and exhibit a high affinity (binding capacity) for the blood group antigens.  Genomic sequencing revealed similarities between the receptor binding domain of SARS-COV-2 and human galectin, making the virus capable of recognizing blood group antigens in humans. The receptor binding domain is part of the spike protein on the surface of the virus that is responsible for infection, and researchers have determined that it also displays a preference for blood group A.

Importantly, the virus does not bind well to blood group A antigens expressed on the red blood cells (RBC’s) in the blood, which may be very fortuitous, as this might have lead to hemolysis (red blood cell destruction) or greater morbidity and mortality. However, experiments revealed that the virus instead binds preferentially to organ tissues expressing a variation of the blood group A sugar. Specifically, SARS-COV-2 binds to epithelial cells in the respiratory tract. This can be understood in the adverse respiratory signs and symptoms associated with pulmonary infection by the virus, such as, cough, shortness of breath, pneumonia, and overall damage to the lungs.

The reason for this difference in affinity is that RBC’s express type II (B1-4) blood group antigens, which differ slightly in structure to the blood group antigens in the respiratory epithelium. Respiratory epithelial cells in the airways of the lungs express type I (B1-3) blood group antigens. The receptor binding domain of SARS-COV-2 binds the type I structure better than the type II structure found in RBC’s.  Interestingly, this was also reported to be the case with SARS-COV-1, the Coronavirus responsible for the SARS (Severe Acute Respiratory Syndrome) outbreak in the early 2000’s. SAR-COV-1 and SAR-COV-2 share over 85% genomic similarity, so it’s not surprising that the receptor binding domain of their spike proteins would both preferentially bind the same blood type.

Interesting facts about blood groups

  • H deficiency is rare; most people have it.
  • O+ is the most common blood type and is found most frequently in Black/African-American and Latinx populations.
  • Caucasians are just as likely to be blood type O+ as they are A+, the second most common blood type in the United States.  
  • AB- followed by B- then AB+ and B+ are the rarest blood types, respectively.

The most significant finding was that SARS-COV-2 recognizes and binds more readily to blood group A antigens, when compared to the other blood groups. Therefore, blood type A is a strong predictor for increased susceptibility to infection by coronavirus SARS-COV-2. As for morbidity and mortality, blood group A has not been associated with increased risk of morbidity or mortality, and the major risks factors for severe disease or death from COVID-19 are age over 65, Caucasian race, and male gender. Though, researchers debate whether blood type A also contributes to the disease severity of COVID-19, it likely plays a role in the progression of the disease.

It is important to note, that while blood type A might increase your risk of contracting SARS-COV-2, there is no blood type that confers protection against the virus and COVID-19. Therefore, it is still necessary to follow all preventative measures such as wearing a mask, social distancing, and hand-washing. Vaccination is also effective at decreasing the risk of severe illness or death from COVID-19 and may also protect against infection in the first place.

References

  1. Shang-Chuen Wu, Connie M. Arthur, Jianmei Wang, Hans Verkerke, Cassandra D. Josephson, Daniel Kalman, John D. Roback, Richard D. Cummings, Sean R. Stowell; The SARS-CoV-2 receptor-binding domain preferentially recognizes blood group A. Blood Adv 2021; 5 (5): 1305–1309. doi: https://doi.org/10.1182/bloodadvances.2020003259
  2. Ramo A, Mehrotra H, Onwubiko I, et al. Correlation between ABO blood groups and disease severity and mortality in hospitalized COVID-19 patients. Presented at: 62nd American Society of Hematology (ASH) Annual Meeting and Exposition; December 5-8, 2020. Abstract 104.

Racial Disparities in Cell Culture

Racial disparity exists in various diseases that occur in human. In particular, the incidence and severity of Prostate Cancer is greater in black men than in white men in the United States. There are intrinsic biological differences that account for the differences in disease development and progression, but these differences are under-studied. Socially, cultural beliefs, as well as, inherent biases and systemic racism contribute to disparities in diagnosis, treatment, and prognosis of prostate cancer in black men on the macrolevel. However, at the biomedical and microlevel, an under appreciation or lack of awareness of the significance of ethnic and racial biological differences has resulted in inadequate diversity in bio-specimens and cell-line models in in vitro research.

Precision medicine is a growing field of interest in the treatment of diseases like cancer, where medicine and therapeutic intervention is tailored to the individuals genotype. However, with that, it is necessary to examine how ethnicity and race influence pathogenesis and progression of a disease, as well as, responsiveness to therapeutic intervention. Currently, the majority of biological samples that are collected from patients are collected from those who are classified as white or of European ancestry. Continue reading

Reinfected & Asymptomatic? That’s a Negative! Coronavirus Case Report and Why Words Matter

By now we are all aware that we are in the midst of a “global public health emergency” due to a novel coronavirus known as SARS-CoV-2, which causes the disease COVID-19. The “novelty” of this virus only refers to the fact that it is new; this is not a romantic title for a deadly virus. In all seriousness, the virus that arose late last year in Wuhan, China has now spread to over 25 other countries and has killed, on average, at least 2.3% of the > 90,000 people it has infected (fatality rate increases in older populations; 8 to 14.8 %). As a result scientists and doctors are racing to catch pace with the virus, not only to develop a vaccine, but to characterize how this coronavirus behaves in its victims.

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Recently, the media has caught wind of some of the reports coming out of the laboratories and clinics, and in what appears to be a hast of misunderstanding have produce more fear and misinformation. The news media has reported that some people who had COVID-19 were re-infected with SARS-CoV-2 after recovering and being discharged from the hospital. Given that there is no precise treatment or approved vaccine, the idea that one could contract the virus again, after just having it, portends that SAR-CoV-2 is insidious; and has sent many people into a panic as its characterizes the virus as being monsterous and unstoppable. It would also mean that SARS-Cov-2 is operating beyond the conventions of virology and immunology.

However, that is not the case and here is why: Continue reading

Laundry Detergent & Allergies

 

A recent study published in 2018 showed that laundry detergent and detergent residue left behind after rinsing may be responsible for the increase in asthma and allergy in humans. Synthetic laundry detergents contain numerous ingredients that are irritants and sensitizers. Surfactants, the substance responsible for creating suds in the wash and bleaches can irritate the skin and respiratory airways leading to the lungs, while fragrances and enzymes can induce sensitization. Researchers found that anionic surfactants disrupt the lining of the airways (bronchial mucosal epithelial barrier) leading to the lungs. Continue reading

Taurine: From Bull Urine to Disease Treatment

bullThere is a common misconception that the popular energy drink RedBull contains urine or sperm from bulls, because it contains taurine. The myth stems from the fact that taurine was originally isolated from Ox bile (bulls and oxen are male cows) in the 1800’s. While initially identified in the bile (produced by the liver) of male cows, taurine is widely found in almost every organ in mammals. Taurine is chemically synthesized and used as an ingredient in infant formula, energy drinks, nutritional supplements, and pet food. Most recently it has been identified for its therapeutic value in the treatment of congestive heart failure and other cardiovascular diseases. It is currently being studied for its further use in the treatment of  other diseases, in particular those relating to  the nervous system, muscles, and mitochondrial disorders.

What is Taurine?

Continue reading

Genetically Engineered Heme in Vegan Meat

Three Masters of Science graduates were overheard talking about the impossible burger— if you haven’t heard about it, it is a vegan-meat substitute produced by Impossible Foods Inc. which palatably mimics an actual ground-beef burger. The one was telling the others, that the burger was not only delicious and filing, but that it smelled and tasted like real beef. When questioned as to what gave it the beef-like sensation, she answered heme, but was unsure of the source of the heme. This was puzzling because most people are familiar with heme being a component of animal blood, and the idea that heme could be vegan or synthetically produced from amino acids in a lab seemed dubious. 

However, as it turns out, heme is ubiquitous to many living organisms, and can be found in  bacteria, fungi, protozoa, higher plants, and animals. In fact, the heme used by Impossible Foods Inc. is derived from a plant heme known as leghemoglobin, that is sourced from soybeans. The leghemoglobin is not directly extracted from the soybean, as extracting leghemoglobin from plant roots is tedious and not cost effective due to low yield. Therefore, to increase productivity, the leghemoglobin is synthesized through genetic engineering. Continue reading

Cold-sore sufferers may be at risk for Alzheimer’s Disease

Alzheimer’s disease (AD), the most common cause of dementia, is a neuro-degenerative disease that causes cognitive decline affecting memory and executive function. While rarely due to genetic mutation, the cause of most cases of Alzheimer’s disease is not known. However, new research indicates that the virus that causes cold-sores (fever-blisters) may also cause or contribute to the development of Alzheimer’s disease. Continue reading

“Obese Microbiota” in Men linked to Lead Exposure

Lead (Pb) is a persistent environmental contaminant that is toxic to humans, primarily in the developmental stages of life. It is believed that environment and nutrition play a role in determining health. Most recently, it has been recognized by the National Institute of Environmental Health Sciences that the interaction between pathogens and toxic agents may contribute to disease development in humans. In fact, epidemiological studies suggest that there may be a correlation between lead exposure and obesity in children and that this effect may be long-lasting, resulting in adulthood obesity.

Perinatal lead exposure in mice

The microbiome has recently been recognized as contributing to health and disruptions in gut microbiota constitution as been associated with chronic illnesses. To investigate the phenomena of Pb-induced obesity, mice were exposed to lead during the perinatal period.  Researchers studied how lead exposure around the time of birth impacted gut microbiota, and then watched to observe whether changes to the microbiome influenced bodyweight.micescale

Microbiome Imbalance

They found that exposure to lead early in development did alter the bacterial composition of the digestive tract.  Pb affected the resilience and diversity of bacteria normally present in the gut; disrupting the balance between aerobic and anaerobic bacterium. Continue reading

STOP! It’s a fact, Seedless Grapes are Natural.

Seedless grapes are in fact as natural and as healthy as grapes with seeds, and unlike popular conjecture, they are not genetically modified organisms. Seedless grapes are used in the production of raisins, jelly, jam, juice, and wine, and are preferred over seeded grapes for reason of edibility.

Grapes have been cultivated for thousands of years. Vitis Vinifera  was domesticated from the wild grape, V. Vinifera Sylvestris, but still bears close morphological and genealogical characteristics. In fact wild grapes can interbreed with domesticated grapes when they encounter each other, however they flower at different times which reduces the likelihood of gene transfer through pollination. Wild grapes are sometimes reintroduced into commercial grape breeding programs, but mutations occur frequently in grape cultivars leading to a diverse genetic pool Seedlessness is the result of a natural mutation that occurred in some cultivated grapes. This natural phenomenon was exploited by vineyards to improve the desirability of grapes by making them easier to grow and consume. Most seedless grapes are bred from the Sultania (Thompson seedless) landrace (traditional isolated cultivars), but also the Black Monukka, Malta, Beauty Seedless, and others. Continue reading

Fat is Alive & Talks to Your Brain

Fat Is Alive

Most people think of fat as being inert, having no real purpose in the body than to keep you warm, and to prevent you from ever having the perfect summer body. The role of fat in the body is so under-appreciated, that when the doctor says, “you need to lose weight”, people often see it as an issue of “body shaming” rather than one of health. This is because fat is not seen as being alive, but as a by-product of too much sugar and starch. While the reality is that fat IS alive, in fact the fat in our bodies is made up of cells called adipocytes, and these cells comprise the functional unit of adipose tissue. Adipocytes and adipose tissue are a part of the endocrine and central nervous system.

Adiocytes – Living Fat

Adipocyte are specialized cells within adipose tissue that contain lipids in the form of multiple round droplets of triglycerides. Triglycerides are the building blocks of fats, as amino acids are the foundation of proteins. Adipocytes simply put are fat cells that transport and produce fat.

There are three types of fat cells: Continue reading