Evolutionary aspects of ABO blood group in humans

ABO Blood Type and Clinical Characteristics Among Japanese Patients With Ulcerative Colitis

Background The ABO blood type has been associated with several digestive diseases. Some evidence has shown an association between ABO blood type and clinical outcomes among Asian patients with Crohn's disease. However, there are no reports about the association between ABO blood type and clinical outcomes in ulcerative colitis (UC). In this study, we aimed to evaluate the association between ABO blood type and clinical characteristics among patients with UC. Methodology The study subjects consisted of 277 Japanese patients with UC. Information on clinical characteristics and ABO blood type data was collected using medical records and a self-reported questionnaire. The information on clinical remission was collected using medical records. The definition of mucosal healing (MH) and partial MH was Mayo endoscopic subscore of 0 or 0-1, respectively. Results Of the enrolled patients, 39.4% (109/277), 18.4% (51/277), 29.2% (81/277), and 13.0% (36/277) had blood types A, B, O, and AB, respectively. The mean current age, age at onset of UC, and body mass index were 51.3 years, 42.1 years, and 22.7 kg/m2, and the proportion of male patients was 59.2% (164/277). The proportion of patients with clinical remission, MH, partial MH, and prednisolone use were 58.1% (161/277), 25.6% (71/277), 63.2% (175/277), and 21.3% (59/277), respectively. Conclusions None of the blood types were associated with any of the variables in this study. Among Japanese patients with UC, ABO blood type might not be associated with clinical characteristics.

Host-Pathogen Interaction: Biology and Public Health

Interactions between host and pathogenic microorganisms are common in nature and have a significant impact on host health, often leading to several types of infections. These interactions have evolved as a result of the ongoing battle between the host's defense mechanisms and the pathogens' invasion strategies. In this chapter, we will explore the evolution of host-pathogen interactions, explore their molecular mechanisms, examine the different stages of interaction, and discuss the development of pharmacological treatments. Understanding these interactions is crucial for improving public health, as it enables us to develop effective strategies to prevent and control infectious diseases. By gaining insights into the intricate dynamics between pathogens and their hosts, we can work towards reducing the burden of such diseases on society.

The Relationship of ABO and Rh Blood Group Types With Severe COVID-19 Disease Mortality in ICU Patients: Insights From a Single-Center Experience in Southern Saudi Arabia

Introduction The global COVID-19 pandemic has triggered an unprecedented public health crisis, emphasizing the need to understand factors influencing disease outcomes. This study explores the role of genetic variations in blood group antigens, particularly ABO and RhD, in shaping mortality rates among critically ill COVID-19 patients in the southern region of Saudi Arabia. Methods Utilizing a retrospective, noninterventional approach, we analyzed medical records of 594 COVID-19 patients admitted to the intensive care unit (ICU) at Aseer Central Hospital from August 2020 to April 2021. The cohort, with a mean age of 60.5 years, consisted of a predominantly male population. Results The study encompassed a diverse age range of 18 to 103 years, with a mean age of 60.5 ± 17.3 years. Of the 594 patients, 398 (67%) were male, and only 5 (0.8%) had a history of smoking. Blood group distribution revealed 275 (48.4%) with O-, 189 (33.3%) with A+, and 51 (9%) with AB- types. Predominant chronic conditions included diabetes mellitus (35.5%). Tragically, 320 patients (54.6%) experienced mortality, with a 100% mortality rate for the B+ blood group and 92.9% for O- blood group. Conclusion This analysis establishes significant statistical links, underscoring the pivotal role of blood type, particularly the Rh factor, in influencing mortality risk among critically ill COVID-19 patients. These findings contribute valuable insights into risk stratification and personalized care for severe cases, emphasizing the importance of genetic considerations in understanding disease outcomes.

ABO blood groups are not associated to gestational diabetes mellitus in Mexican women

OBJECTIVES

Some studies show an increased risk of gestational diabetes mellitus for ABO blood groups. Others find a lower risk or do not identify any association. Inconsistencies may be due to the heterogeneity in the control for confounding variables. We determined the association between ABO blood groups and gestational diabetes mellitus in Mexican women, controlling for gravidity and age, pre-pregnancy body mass index, fasting glucose at the first trimester, and first-degree relative with diabetes.

METHODS

This case-control study was conducted from February 2019 to December 2021 in Monterrey, Mexico, with 185 cases (women with gestational diabetes mellitus) and 530 controls. ABO blood groups and other variables were obtained from the clinical records. A multivariate binary logistic regression was used for estimating association. Two models were run, one for primigravidae and another for non-primigravidae. A p-value < 0.05 was significant.

RESULTS

The ABO blood groups were O (69.4%), A (22.2%), B (6.7%), and AB (1.7%), with no differences between cases and controls (p = 0.884). No association was found between ABO blood groups and gestational diabetes mellitus, in primigravidae or non-primigravidae.

CONCLUSION

ABO blood groups were not associated with an increased risk of gestational diabetes mellitus in Mexican women, independent of gravidity and well-known risk factors.

Effects of host blood on mosquito reproduction

Female mosquitoes require blood from their host for egg development. However, the relationship between the composition of host blood and mosquito reproduction, and whether and how this is linked to host selection, remain unclear. A better understanding of these issues is beneficial for mass-rearing of mosquitoes for vector control. This review provides an overview of the currently known effects of blood constituents on mosquito reproduction. Furthermore, it highlights knowledge gaps and proposes new avenues for investigation. We recommend that research efforts be focused on physiological differences between generalist and specialist mosquito species as models to investigate if and how host preference correlates with reproductive output.

Babesia divergens Shows Equal Predilection for Human ABO Blood Types in an In Vitro Erythrocyte Preference Assay

Babesia is spread to humans via ticks or blood transfusions. Severity of Plasmodium falciparum malaria is strongly correlated to the ABO blood group of the patient. Babesia divergens is an intraerythrocytic parasite with many similarities to malaria, but the impact of ABO on the susceptibility to and progression of the infection in humans is unknown. We have now cultured B. divergens in human group A, B and O erythrocytes in vitro and measured rates of multiplication. The predilection for the different erythrocyte types was also determined using an in vitro erythrocyte preference assay when the parasites were grown in group A, B or O erythrocytes over time and then offered to invade differently stained erythrocytes of all the blood types at the same time. The results showed no difference in multiplication rates for the different blood types, and the parasite exhibited no obvious morphological differences in the different blood types. When cultured first in one blood type and then offered to grow in the others, the preference assay showed that there was no difference between the A, B or O blood groups. In conclusion, this indicates that individuals of the different ABO blood types are likely to be equally susceptible to B. divergens infections.

Recent advances in the identification of related factors and preventive strategies of hip fracture

Hip fracture is the most devastating type of osteoporosis-related fracture, and is a major worldwide public health problem with a high socioeconomic burden, morbidity rate, and mortality rate. Thus, it is crucial to uncover the risk factors and protective factors to create a hip fracture prevention strategy. In addition to a briefly review of some well accepted risk and protective factors of hip fracture, this review mainly summarized the recent advances in the identification of emerging risk or protective factors for hip fracture, in terms of regional differences in medical services, diseases, drugs, mechanical load, neuromuscular mass, genes, blood types, cultural differences. This review provides a comprehensive review of the associated factors and effective prevention measures for hip fracture, and discusses issues that need further investigation. These issues include the determination of the influencing mechanism of risk factors triggering hip fracture and their interlinked correlation with other factors, as well as the confirmation or correction of emerging factors associated with hip fracture, particularly those that are still controversial. These recent findings will aid in optimizing the strategy for preventing hip fracture.

Clinical application of ABO blood typing

BACKGROUND

The ABO blood group is closely related to clinical blood transfusion, transplantation, and neonatal hemolytic disease. It is also the most clinically significant blood group system in clinical blood transfusion.

OBJECTIVE

The purpose of this paper is to review and analyze the clinical application of the ABO blood group.

METHODS

The most common ABO blood group typing methods in clinical laboratories are hemagglutination test and microcolumn gel test, while genotype detection is mainly adopted in clinical identification of suspicious blood types. However, in some cases, the expression variation or absence of blood type antigens or antibodies, experimental techniques, physiology, disease, and other factors affect the accurate determination of blood types, which may lead to serious transfusion reactions.

RESULTS

The mistakes could be reduced or even eliminated by strengthening training, selecting reasonable identification methods, and optimizing processes, thereby improving the overall identification level of the ABO blood group. ABO blood groups are also correlated with many diseases, such as COVID-19 and malignant tumors. Rh blood groups are determined by the RHD and RHCE homologous genes on chromosome 1 and are classified as Rh negative or positive according to the D antigen., the agglutination method is often used in clinical settings, while genetic and sequencing methods are often used in scientific research.

CONCLUSION

Accurate ABO blood typing is a critical requirement for the safety and effectiveness of blood transfusion in clinical practice. Most studies were designed for investigating rare Rh blood group family, and there is a lack of research on the relationship between Rh blood groups and common diseases.

ABO blood group antigens and differential glycan expression: Perspective on the evolution of common human enzyme deficiencies

Enzymes catalyze biochemical reactions and play critical roles in human health and disease. Enzyme variants and deficiencies can lead to variable expression of glycans, which can affect physiology, influence predilection for disease, and/or directly contribute to disease pathogenesis. Although certain well-characterized enzyme deficiencies result in overt disease, some of the most common enzyme deficiencies in humans form the basis of blood groups. These carbohydrate blood groups impact fundamental areas of clinical medicine, including the risk of infection and severity of infectious disease, bleeding risk, transfusion medicine, and tissue/organ transplantation. In this review, we examine the enzymes responsible for carbohydrate-based blood group antigen biosynthesis and their expression within the human population. We also consider the evolutionary selective pressures, e.g. malaria, that may account for the variation in carbohydrate structures and the implications of this biology for human disease.

Association of Plasma Metabolites and Lipoproteins with Rh and ABO Blood Systems in Healthy Subjects

This study investigated the associations between the levels of 27 plasma metabolites, 114 lipoprotein parameters, determined using nuclear magnetic resonance spectroscopy, and the ABO blood groups and the Rhesus (Rh) blood system in a cohort of n = 840 Italian healthy blood donors of both sexes. We observed good multivariate discrimination between the metabolomic and lipoproteomic profiles of subjects with positive and negative Rh. In contrast, we did not observe significant discrimination for the ABO blood group pairwise comparisons, suggesting only slight metabolic differences between these group-specific metabolic profiles. We report univariate associations (P-value < 0.05) between the subfraction HDL1 related to Apo A1, the subfraction HDL2 related to cholesterol and phospholipids, and the particle number of LDL2 related to free cholesterol, cholesterol, phospholipids, and Apo B and the ABO blood groups; we observed association of the lipid main fraction LDL4 related to free cholesterol, triglycerides, and Apo B; creatine; the particle number of LDL5; the subfraction LDL5 related to Apo B; the particle number of LDL4; and the subfraction LDL4 related to Apo B with Rh blood factors. These results suggest blood group-dependent (re)shaping of lipoprotein metabolism in healthy subjects, which may provide relevant information to explain the differential susceptibility to certain diseases observed in different blood groups.

Burden of malaria infection among individuals of varied blood groups in Kenya

Background

The ABO blood groups consist of A, B, and H carbohydrate antigens, which regulate protein activities during malaria infection in humans. Understanding the interplay between the malaria parasite and blood group antigens is essential in understanding new interventions to reduce the global burden of malaria. This study assessed the burden of malaria infection among individuals with varying blood groups seeking treatment at selected hospitals in Kenya.

Methods

A total of 366 samples from an ongoing malaria surveillance study were diagnosed for malaria by microscopy and further typed for blood group using ABO blood grouping. Age and sex were recorded in a data sheet, and analysed using R software version 4. Groups’ proportions (blood group, malaria infection, age and sex) were compared using Pearson’s Chi-square and Fischer exact tests. Wilcoxon and Kruskal-Wallis tests were performed and P-value < 0.05 was considered significant after Bonferroni correction for multiple comparisons. To understand the effect of each blood group on parasitaemia, multivariate logistic regression was used to model ABO blood group in relation to parasitaemia.

Results

Of the 366 samples analysed, 312 were malaria positive, mean age was 9.83 years (< 5 years n = 152 (48.41%), 6 to 17 years n = 101 (32.16%) and > 18 years n = 61 (19.43%)). Malaria prevalence was higher among females than males, 54.46% and 45.54%, respectively. Kisumu enrolled the highest number 109 (35%)) of malaria cases, Kombewa 108 (35%), Malindi 32 (10%), Kisii 28 (9%), Marigat 23 (7%), and Kericho 12 (4%). Blood group O⁺ was the most prevalent among the enrolled individuals (46.50%), A⁺ (27.71%), B⁺ (21.02%) and AB⁺ (4.78%) respectively. Compared to blood group O+, blood group B⁺ individuals were (14%) were more likely to habour Plasmodium falciparum infection as opposed to A⁺ and AB⁺ individuals, that were 7% and 20%, respectively,. Those living in malaria-endemic zones presented with higher parasite densities compared to those living in malaria-epidemic (p = 0.0061). Individuals bearing B + blood group are more likely to habour high parasitaemia compared to O + blood group bearers (OR = 4.47, CI = 1.53–13.05, p = 0.006).

Conclusion

Individuals of blood group B harbour high parasitaemia compared with the blood group O, Additionally, blood group A and B present with symptoms at lower parasitaemia than blood group O. Regardles of malaria transmission zones, individuals from endemic zones showed up with high parasitaemia and among them were more individuals of blood groups A and B than individuals of blood group O. Implying that these individuals were more at risk and require additional attention and effective case management.

Garphical Abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s12936-022-04251-1.

Associations of Clinical Factors and Blood Groups With the Severity of COVID-19 Infection in Makkah City, Saudi Arabia

Context

The possible associations between the different blood groups and clinical factors with COVID-19 infection among patients in Makkah city.

Objective

To investigate the relationship between ABO blood groups and COVID-19 infection in patients who were tested positive and to elucidate the most common ABO blood groups with a higher infectivity of COVID-19 and disease association.

Materials and Methods

This was an observational cross-sectional study that included COVID-19 patients diagnosed with PCR and who were hospitalized in Al-Noor Specialist Hospital (Makkah) during the period between March to November 2020. The ABO and Rhesus blood groups alongside the clinical characteristics were determined and retrieved from medical records and HESN of the Ministry of Health of the Kingdom of Saudi Arabia (KSA).

Results

The overall confirmed COVID-19 cases included in this study were 1,583 patients who underwent positive PCR testing between March and November 2020. The frequencies of blood groups were as follows: group O⁺ (37%), group A⁺ (29.2%), group B⁺ (22.6%), group AB⁺ (5.1%), group O^- (2.8%), group B^- (1.8%), group A^- (1.1%), and group AB^- (0.4%). However, no significant correlations were observed for ABO groups and Rh types with the severity of COVID-19 illness. Conversely, signs and symptoms of respiratory distress syndrome (RDS), pneumonia, and respiratory failure symptoms, alongside a history of diabetes mellitus, hypertension, chronic kidney diseases, and congestive heart failure significantly increased the risk of death from COVID-19 infection. Moreover, the rates of fever, cough, and asthma were markedly lower in the deceased group compared with the recovered group of patients.

Conclusion

The association between the different blood groups with the prevalence and mortality of COVID-19 among infected patients has yet to be elucidated as we found no significant differences in the observed versus expected distribution of ABO phenotypes among the included cases. The prevalence of RDS, pneumonia, and respiratory failure was found higher among hospitalized COVID-19 patients in the deceased group. However, other factors such as fever, cough, and asthma appeared to be more significantly lower than in the recovered group.

The Clinical Utility of ABO and RHD Systems as Potential Indicators of Health Status, a Preliminary Study in Greek Population

Objective: The objective of this study is to further highlight the differences between different ABO blood groups and Rhesus types with health biomarkers. Methods: In total 150 active healthy blood donors participated in our study comprising of 80 males from 19–61 years and 70 females aged from 21 to 64. Participants carrying blood group A were 55 individuals, blood group B 32, blood group O 51, and blood group AB 12, RHD+ 132, and RHD- 18. All the volunteer regular blood donors were selected recognizing them as a healthy population excluding drug and supplements intake. Their blood samples were analyzed just before blood donation for biochemical, hematological, and antioxidant markers. Statistical computations were performed using the SPSS tool, specifically, the one-way ANOVA test, Chi-square statistics, and logistic regression were used as statistical models. Results: O blood donors presented better iron absorption and the worst lipid profile. Indeed, a significant trend of high atheromatic index values revealed an increased risk for hyperlipidemia, in contrast with blood group A presenting a better lipid profile with lower atheromatic index values. There was also a gender related association for blood group A compared with O that was further highlighted using binary logistic regression. Conclusion: In this study, a significant difference was observed among the ABO blood groups in several of the examined biochemical and hematological biomarkers. O blood group appeared different behavior in comparison to all the tested blood groups and furthermore the RHD-group presented a better lipid profile in comparison to the RHD+ group. In order to obtain a more comprehensive view of the correlation between the ABO blood group and biochemical markers, further studies are required.

ABO Blood Type Is Associated with Thrombotic Risk in Patients with Nonvalvular Atrial Fibrillation

Blood type is reportedly correlated with the occurrence of cardiovascular diseases, presumably because of its effect on thrombogenicity. However, the relationship between blood type and thrombotic complications in atrial fibrillation (AF) remains unclear. This retrospective study analyzed the blood types of 1170 AF patients (mean age, 70 years; 58% men) who were followed up for up to 4 years. Patients with greater than mild mitral stenosis or prosthetic valves were excluded. The cohort included 305 (26%) type O, 413 (35%) type A, 333 (28%) type B, and 119 (10%) type AB patients. The primary endpoint of major adverse cerebrovascular events (MACE) occurred in 52 (4.4%) patients. When longitudinal outcomes were plotted, AB blood type patients had worse prognosis than non-AB blood type patients (p = 0.039), particularly type O blood patients (p = 0.049). Multivariate Cox regression analysis revealed that AB blood type was associated with higher MACE rates (adjusted hazard ratio, 2.01; 95% confidence interval, 1.01–4.00; p = 0.048) than non-AB blood types independent of anticoagulation therapy duration or CHA2DS2-VASc score. These indicate that AF patients with AB blood type are at an increased risk of MACE compared to those with non-AB blood type independent of the duration of anticoagulation or the CHA₂DS₂-VASc score.

A Novel Mutation Eliminates GATA-1 and RUNX1-Mediated Promoter Activity in Galactosyltransferase Gene

Introduction

Mutations in the promoter region and exons of ABO gene may cause changes in the expression of blood group antigens, often showing a weak ABO phenotype. Here, we identified a novel weak ABO subgroup allele that caused B_el phenotype and explored its mechanisms.

Methods

The ABO phenotype of subjects (Chinese Han nationality) was classified by serological method. The plasma activity of erythrocyte glycosyltransferase was detected by the phosphate coupling method. ABO subtype genotyping was performed by PCR-SSP and exon sequencing. The activity of the promoter was evaluated by a dual-luciferase reporter assay.

Results

We identified a mutation exon 1 c.15_16insTGTTG of the B allele in a B_el subject. Genealogical investigation showed that the mutation was inherited from her mother. The mutation was located in the promoter region of the ABO gene. The dual-luciferase reporter assay showed that the mutation inactivated GATA-1 and RUNX1-mediated activity of the ABO gene promoter, leading to a decrease in the expression and activity of B glycosyltransferase.

Conclusion

A novel B_var ABO subgroup allele was identified. The novel mutation can reduce the promoter activity that activated by GATA-1 and RUNX1, subsequently causing the B_el phenotype.

ABO blood group and Rh factor distributions in patients with epilepsy

OBJECTIVE

We investigated the ABO blood group and Rh factor distributions in patients with epilepsy (PWE) in comparison with a comparator population.

METHODS

We recruited patients who were admitted to the epilepsy ward at Namazi hospital in Shiraz, Iran, in 2021. We classified epilepsies into two categories: focal vs. generalized. We also used the anonymous data from Fars Blood Transfusion Organization from 15th June to 30th June, 2021, as the comparator population (to estimate the frequencies of various blood types in the cohort from which PWE were recruited).

RESULTS

Overall, 390 PWE were included [131 (33.6%) with generalized and 259 (66.4%) with focal epilepsy]. We also included 7672 blood donors [from Fars Blood Transfusion Organization data]. The O phenotype had the highest frequencies in both PWE and the comparator population, followed by A, B, and AB blood groups. Similar patterns were observed in patients with focal and generalized epilepsy. With regard to Rh blood group, the Rh-positive phenotype was more prevalent in all groups. The differences between the groups were not significant in any of the comparisons.

CONCLUSION

While we did not observe any significant associations between blood group and epilepsy in the current study, previous studies have demonstrated compelling evidence that risks of some neuropsychiatric disorders are related to the chemistry of blood, including blood group classification. The issue of the association between epilepsy and blood group should be investigated in large and well-designed studies in the future.

Association of O blood type with the prognosis of acute necrotizing encephalopathy in childhood: A single-center cohort study

BACKGROUND

Acute necrotizing encephalopathy (ANE) of childhood is a rare but critical disease with global distribution. Few studies have focused on investigating the relationship between O blood type and the prognosis of ANE.

METHODS

We analyzed retrospectively the data of patients with ANE admitted to the Beijing Children's Hospital from March 2012 to February 2019. Baseline data, clinical characteristics, examination, treatment, and prognosis of O blood group were compared with those of the non-O blood group. Cox regression was used to observe the independent prognostic factors in ANE.

RESULTS

Thirty-one ANE patients were recruited, and 8 (25.8%) of these patients were in the O blood group. The rest (n = 23; 74.2%) were in the non-O blood group. No significant differences were found in the demographic characteristics, clinical features, examinations, and treatments between the two groups (p > 0.05). At 28 days after discharge, the overall survival rate of the O blood group was significantly higher than that of the non-O blood group (χ² = 5.630, p = 0.018). At 1 year after discharge, the survival quality of the O blood group was higher than that of the non-O blood group (p = 0.006). After adjusting for the confounding factors, Cox regression analysis showed that O blood type might be a protective factor in ANE [hazard ratio = 0.283, 95% CI = 0.081-0.988; p = 0.048].

CONCLUSIONS

O blood type may be a protective factor for patients with ANE.

ABO blood group and risk of malaria during pregnancy: a systematic review and meta-analysis

The association between the ABO blood group and the risk of malaria during pregnancy has not been clearly established. The present study summarised relevant knowledge and reassessed the association through meta-analysis. Articles in MEDICINE and PubMed published before 30 November 2021 were searched. Five studies satisfied the inclusion criteria and were enrolled in the meta-analysis. It was shown that primiparae with different ABO blood group, multiparae with blood group A and non-A, AB and non-AB had a comparable risk of malaria. However, multiparae with blood group B had a significantly higher risk than non-B group [odds ratio (OR) = 1.23, 95% confidence interval (CI) was 1.01 to 1.50, P = 0.04], while multiparae with blood group O had a significantly lower risk than non-O group (OR = 0.78, 95% CI was 0.63 to 0.97, P = 0.03). Therefore, the ABO blood group may not result in a different risk of malaria in primiparae. Blood group B is potentially a risk factor while blood group O is a protective factor for multiparae.

ABO and Rhesus Blood Groups in Acute Puumala Hantavirus Infection

Puumala hantavirus (PUUV) causes hemorrhagic fever with renal syndrome. We aimed to evaluate whether ABO and rhesus blood groups associate with the susceptibility or the severity of PUUV infection. We analyzed blood groups in 289 adult patients treated in Tampere University hospital due to PUUV infection during the years 1982–2017. Patients’ blood group distribution was compared to that of healthy, voluntary blood donors living in the Tampere University Hospital responsibility area (n = 21,833). The severity of PUUV infection, as judged by the severity of acute kidney injury (AKI), thrombocytopenia, inflammation, capillary leakage, and the length of hospital care, was analyzed across the groups. The ABO and rhesus blood group distributions did not differ between the patients and blood donors. Patients with non-O blood groups had lower systolic blood pressure compared to patients with blood group O, but there was no difference in other markers of capillary leakage or in the severity of AKI. Minor deviations in the number of platelets and leukocytes were detected between the O and non-O blood groups. To conclude, patients with blood group O may be less susceptible to hypotension, but otherwise blood groups have no major influences on disease susceptibility or severity during acute PUUV infection.

The Usefulness of Rare Blood Group Systems in the Risk Determination for Severe COVID-19

The newly identified human coronavirus was named severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), based on a detailed analysis of clinical manifestation. It was reported that blood type O individuals were less likely to become infected by SARS-CoV, while blood type A individuals have an increased risk of severe illness. The Forssman antigen, or Forssman glycolipid synthase (FS), was first described in 1911 by John Frederick Forssman. Blood type A/B glycosyltransferases (AT/BTs) and Forssman glycolipid synthase (FS) are encoded by the evolutionarily related ABO (A/B alleles) and GBGT1 genes. In this article, based on published studies about the pathogenesis of the COVID-19, we hypothesize the possible relationship between the COVID-19 infection and rare blood type systems, such as the Forssman antigen system.

Genomic Association vs. Serological Determination of ABO Blood Types in a Chinese Cohort, with Application in Mendelian Randomization

ABO blood system is an inborn trait determined by the ABO gene. The genetic-phenotypic mechanism underneath the four mutually exclusive and collectively exhaustive types of O, A, B and AB could theoretically be elucidated. However, genetic polymorphisms in the human populations render the link elusive, and importantly, past studies using genetically determined rather than biochemically determined ABO types were not and could not be evaluated for the inference errors. Upon both blood-typing and genotyping a cohort of 1008 people of the Han Chinese population, we conducted a genome-wide association study in parallel with both binomial and multinomial log-linear models. Significant genetic variants are all mapped to the ABO gene, and are quantitatively evaluated for binary and multi-class classification performances. Three single nucleotide polymorphisms of rs8176719, rs635634 and rs7030248 would together be sufficient to establish a multinomial predictive model that achieves high accuracy (0.98) and F1 scores (micro 0.99 and macro 0.97). Using the set of identified ABO-associated genetic variants as instrumental variables, we demonstrate the application in causal analysis by Mendelian randomization (MR) studies on blood pressures (one-sample MR) and severe COVID-19 with respiratory failure (two-sample MR).

The Association Between ABO Blood Group and Preeclampsia: A Systematic Review and Meta-Analysis

Objective: This meta-analysis comprehensively evaluated the association between ABO blood group and the risk of preeclampsia (PE).

Design: Systematic review and meta-analysis.

Data sources: PubMed, Web of Science, and ScienceDirect databases from their inception to September 23, 2020.

Methods: Pooled odds ratios (ORs) with 95% confidence intervals (CIs) were obtained through random-effects and fixed-effects models according to heterogeneity. Meta-regression analysis was applied to explore the source of heterogeneity. We conducted a subgroup analysis by the publication year, study design, state, and Newcastle-Ottawa Scale (NOS) score. In addition, we calculated the rate of each ABO blood group in PE by total pooled effects.

Results: A total of 12 articles with 714,153 patients were included in our analysis. Compared with people without PE (control group), the O blood group presented a lower risk of PE (OR 0.95, 95% CI 0.93–0.97). The AB (OR 1.46, 95% CI 1.12–1.91) blood group presented a higher risk. However, the total pooled OR and 95% CI for the A (OR 1.02, 95% CI 0.90–1.16) and B (OR 1.02, 95% CI 0.98–1.05) blood groups were not significant. The funnel plot and linear regression equation showed that there was no publication bias for the O, A, or B blood groups (all P > 0.05). However, the funnel plot and linear regression equation for the AB blood group were obviously asymmetric (P < 0.05), and the publication bias persisted even after the trim-and-fill method was applied (P < 0.05). Multivariable meta-regression analysis did not find a specific source of heterogeneity. The A blood group showed an association with early-onset PE (OR 0.53, 95% CI 0.33–0.83), and the other blood groups showed no significant differences. In PE, the rates of the O, A, B, and AB blood groups decreased gradually (0.39, 0.33, 0.19, 0.07).

Conclusion: These findings suggest that pregnant women with AB blood group are more likely to develop PE, and more attention should be paid to AB blood group whose blood pressure is high but not sufficient to diagnose PE.

Systematic Review Registration: Prospero CRD42021227930.

A longitudinal study of convalescent plasma (CCP) donors and correlation of ABO group, initial neutralizing antibodies (nAb), and body mass index (BMI) with nAb and anti-nucleocapsid (NP) SARS-CoV-2 antibody kinetics: Proposals for better quality of CCP collections

INTRODUCTION

Little is known about the neutralizing (nAb) and binding antibody kinetics in COVID-19 convalescent plasma donors, especially during the first 100 days after disease onset.

MATERIALS AND METHODS

A cohort of previously RT-PCR positive (detected by nasopharyngeal swab during the acute phase), male convalescent patients, all with mild symptoms, were enrolled in serial blood sample collection for a longitudinal nAb titers and anti-nucleocapsid (NP) antibodies (IgM, IgG and IgA) evaluation. NAbs were detected by a cytopathic effect-based virus neutralization test (CPE-based VNT), carried out with SARS-CoV-2 (GenBank: MT350282).

RESULTS

A total of 78 male volunteers provided 316 samples, spanning a total of 4820 days of study. Although only 25% of donors kept nAb titers ≥160 within 100 days after the onset of disease, there was >75% probability of sustaining nAb titers ≥160 in volunteers whose initial nAb titer was ≥1280, weight ≥ 90 kg or obese, according to their body mass index (BMI), as evidenced by Kaplan-Meier analysis and Cox hazard regression (all p < .02). There was no correlation between the ABO group, ABO antibody titers and persistent high nAb titers. High IgG anti-NP (S/CO ≥5.0) is a good surrogate for detecting nAb ≥ 160, defined by the ROC curve (sensitivity = 90.5%; CI95%: 84.5%-94.7%).

CONCLUSION

Selection of CCP donors for multiple collections based on initial high nAb titers (≥1280) or BMI ≥ 30 kg/m2 provides a simple strategy to achieve higher quality in CCP programs. High IgG anti-NP levels can also be used as surrogate markers for high nAb screening.

An agnostic study of associations between ABO and RhD blood group and phenome-wide disease risk

Background

There are multiple known associations between the ABO and RhD blood groups and disease. No systematic population-based studies elucidating associations between a large number of disease categories and blood group have been conducted.

Methods

Using SCANDAT3-S, a comprehensive nationwide blood donation-transfusion database, we modeled outcomes for 1217 disease categories including 70 million person-years of follow-up, accruing from 5.1 million individuals.

Results

We discovered 49 and 1 associations between a disease and ABO and RhD blood groups, respectively, after adjustment for multiple testing. We identified new associations such as a decreased risk of kidney stones and blood group B as compared to blood group O. We also expanded previous knowledge on other associations such as pregnancy-induced hypertension and blood groups A and AB as compared to blood group O and RhD positive as compared to negative.

Conclusions

Our findings generate strong further support for previously known associations, but also indicate new interesting relations.

Funding

Swedish Research Council.

Association of Blood Subgroups With PCR Test Positivity and Lung Involvement in Patients With COVID-19

Objective The goal of this study was to investigate whether blood group type caused susceptibility to COVID-19 infection. Methods Two hundred and eleven consecutive patients admitted with various symptoms associated with COVID-19 were included. We compared the AB0 and Rh subgroup distributions between patients with a positive polymerase chain reaction (PCR) test result and the patients without. We compared the AB0 and Rh subgroup distributions between patients with lung involvement and patients without. Additionally, comparisons were performed between the patients both with positive PCR result and lung involvement, and the patients with a negative PCR result. Results No significant difference of ABO and Rh subgroup distributions was evident between patients with and without a positive PCR test result (p=0.632 and p=0.962). No significant difference of ABO and Rh subgroup distributions was evident between the patients with and without lung involvement (p=0.097 and p=0.797). No significant difference of ABO and Rh subgroup distributions was evident among patients both with PCR positivity and lung involvement, patients with only PCR positivity, and the patients with negative PCR test results (p=0.3 and p=0.993). Conclusion All blood group types seem to have an equal risk of COVID-19 infection. Everyone should follow the precautions to avoid the COVID-19 infection.

Anti-A and SARS-CoV-2: an intriguing association

Background

Blood groups and anti‐A isohemagglutinin may be involved in susceptibility to SARS‐CoV‐2 infection.

Materials and Methods

We retrospectively studied 268 COVID‐19 convalescent plasma donors and 162 COVID‐19 inpatients (total 430 subjects, confirmed by RT‐PCR) and 2,212 healthy volunteer first‐time blood donors as a control group. These were further divided into two groups: those with anti‐A (blood types O and B) and those without it (types A and AB). Titres of nucleoproteins, and neutralizing SARS‐CoV‐2 antibody were measured in the convalescent plasma donors and inpatients. Multivariate logistic regression and non‐parametric tests were applied.

Results

Persons having types O or B showed less infection prevalence than those of types A or AB (OR = 0·62, 95% CI 0·50–0·78; P < 0·001), but there was no difference when COVID‐19 inpatients were analysed. Immunoglobulins M, G and A were lower in COVID‐19 subjects of types O or B group than those of A or AB (0·16 vs. 0·19; P = 0·03, 2·11 vs. 2·55; P = 0·02, 0·23 vs. 0·32; P = 0·03, respectively).

Conclusion

In this retrospective cohort, COVID‐19 individuals were less likely to belong to blood types O and B, and also had lower SARS‐CoV‐2 antibody titres than A and AB individuals. COVID‐19 severity did not associate with the blood groups.

Association between ABO blood groups and susceptibility to COVID-19: profile of age and gender in Iraqi patients

Background

A case-control study was performed to examine age, gender, and ABO blood groups in 1014 Iraqi hospitalized cases with Coronavirus disease 2019 (COVID-19) and 901 blood donors (control group). The infection was molecularly diagnosed by detecting coronavirus RNA in nasal swabs of patients.

Results

Mean age was significantly elevated in cases compared to controls (48.2 ± 13.8 vs. 29.9 ± 9.0 year; probability [p] < 0.001). Receiver operating characteristic analysis demonstrated the predictive significance of age in COVID-19 evolution (Area under curve = 0.858; 95% CI: 0.841 - 0.875; p < 0.001). Males outnumbered females in cases (60.4 vs. 39.6%) and controls (56 vs. 44%). Stratification by age group (< 30, 30 - 39, 40 - 49 and ≥ 50 years) revealed that 48.3% of cases clustered in the age group ≥ 50 years. ABO blood group analysis showed that group A was the most common among cases, while group O was the most common among controls (35.5 and 36.7%, respectively). Blood groups A (35.5 vs. 32.7; corrected p [pc] = 0.021), A+AB (46.3 vs. 41.7%; pc = 0.021) and A+B+AB (68.0 vs. 63.3%; pc = 0.007) showed significantly elevated frequencies in cases compared to controls. Logistic regression analysis estimated odds ratios (ORs) of 1.53 (95% confidence interval [CI]: 1.16 - 2.02), 1.48 (95% CI: 1.14 - 1.93) and 1.50 (95% CI: 1.17 - 1.82) for blood groups A, A+AB and A+B+AB, respectively. Blood group frequencies showed no significant differences between age groups of cases or controls. Regarding gender, male cases were marked with increased frequency of group A (39.9 vs. 28.9%) and decreased frequency of group O (25.9 vs. 41.0%) compared to female cases. Independent re-analysis of ABO blood groups in male and female cases demonstrated that group A was increased in male cases compared to male controls (39.9 vs. 33.1%; OR = 1.65; 95% CI: 1.24 - 2.21; pc = 0.006). On the contrary, no significant differences were found between females of cases and controls.

Conclusions

The study results indicated that blood group A may be associated with an increased risk of developing COVID-19, particularly in males.

Non-O blood group is associated with lower risk of in-hospital mortality in non-surgically managed patients with type A aortic dissection

BACKGROUND

The association between different ABO blood groups and mortality of aortic dissection (AD) remains controversial. This study aimed to examine whether different ABO blood groups affect the prognosis of AD.

METHODS

Demographic and clinical data were collected from 877 patients diagnosed with AD from 2015 to 2019 in the First Affiliated Hospital of Shantou University Medical College. The association between in-hospital mortality of AD patients and ABO blood group was analyzed using Cox proportional hazards regression models.

RESULTS

This retrograde cohort study demonstrated that for 877 patients, male gender, non-O blood group, Stanford type B AD (TBAD), higher presenting systolic and diastolic blood pressure, and being a recipient of aortic arch replacement surgery (surgery) or endovascular stent-graft implantation (stent-graft) were associated with decreased in-hospital mortality of AD. In Cox proportional hazards models, non-O blood group was associated with lower risk of early mortality regardless of adjustment (HR = 0.668, 95% confidence interval [CI] 0.473-0.944 before adjustment, HR = 0.662, 95% CI 0.468-0.935 after adjustment for age and sex, and HR = 0.641, 95% CI 0.453-0.906 after adjustment for AD types, SBP and surgery). Further analyses revealed that for patients diagnosed with type A AD (TAAD), non-O blood group renders a significant 34.3% decrease in the risk of in-hospital mortality compared with blood group O. Specifically, this difference in mortality risk was found among TAAD patients who did not undergo surgery (HR = 0.579, 95% CI 0.377-0.889), rather than those who did. There was no significant difference in early mortality for patients with TBAD, whether or not stent-grafts were implanted.

CONCLUSIONS

Non-O blood type decreases the risk of in-hospital mortality, especially for TAAD, in AD patients without surgical intervention. More attention must be paid to blood type O TAAD patients without surgical interventions, and early surgical intervention may be an effective means to decrease in-hospital mortality of TAAD.

A phenome-wide association study of ABO blood groups

BACKGROUND

ABO blood group is associated with differences in lifespan, cardiovascular disease, and some cancers, for reasons which are incompletely understood. To gain sex-specific additional insight about potential mechanisms driving these common conditions for future interventions, we characterized associations of ABO blood group antigen across the phenotype sex-specifically.

METHODS

We performed a phenome-wide association study (PheWAS) assessing the association of tag single nucleotide polymorphisms (SNPs) for ABO blood group antigens (O, B, A1, and A2) with 3873 phenotypes.

RESULTS

The tag SNP for the O antigen was inversely associated with diseases of the circulatory system (particularly deep vein thrombosis (DVT)), total cholesterol, low-density lipoprotein cholesterol (LDL-C), and ovarian cancer, and positively associated with erythrocyte traits, leukocyte counts, diastolic blood pressure (DBP), and healthy body composition; the tag SNP for the A1 antigen tended to have associations in reverse to O. Stronger associations were more apparent for men than women for DVT, DBP, leukocyte traits, and some body composition traits, whereas larger effect sizes were found for women than men for some erythrocyte and lipid traits.

CONCLUSION

Blood group has a complex association with cardiovascular diseases and its major risk factors, including blood pressure and lipids, as well as with blood cell traits and body composition, with some differences by sex. Lower LDL-C may underlie some of the benefits of blood group O, but the complexity of associations with blood group antigen suggests overlooked drivers of common chronic diseases.

Evaluating of the association between ABO blood groups and coronavirus disease 2019 (COVID-19) in Iraqi patients

Background

Susceptibility to the pandemic coronavirus disease 2019 (COVID-19) has recently been associated with ABO blood groups in patients of different ethnicities. This study sought to understand the genetic association of this polymorphic system with risk of disease in Iraqi patients. Two outcomes of COVID-19, recovery and death, were also explored. ABO blood groups were determined in 300 hospitalized COVID-19 Iraqi patients (159 under therapy, 104 recovered, and 37 deceased) and 595 healthy blood donors. The detection kit for 2019 novel coronavirus (2019-nCoV) RNA (PCR-Fluorescence Probing) was used in the diagnosis of disease.

Results

Mean age was significantly increased in patients compared to controls (49.8 ± 11.7 vs. 28.9 ± 6.6 years; p < 0.001). A similar observation was made in recovered (42.1 ± 10.4 vs. 28.9 ± 6.6 years; p < 0.001) and deceased (53.6 ± 9.7 vs. 28.9 ± 6.6 years; p < 0.001) cases. The mean age was also significantly increased in deceased cases compared to recovered cases (53.6 ± 9.7 vs. 42.1 ± 10.4 years; p < 0.001). There were gender-dependent differences in COVID-19 prevalence. The percentage of COVID-19 was higher in males than in females (all cases: 59.7 vs. 40.3%; recovered cases: 55.8 vs. 44.2%). Such male-gender preponderance was more pronounced in deceased cases (67.6 vs. 32.4%). Logistic regression analysis revealed that groups AB and B + AB were significantly associated with increased risk to develop COVID-19 (OR = 3.10; 95% CI 1.59-6.05; pc = 0.007 and OR = 2.16; 95% CI 1.28-3.63; pc = 0.028, respectively). No ABO-associated risk was observed in recovered cases. On the contrary, groups A (OR = 14.60; 95% CI 2.85-74.88; pc = 0.007), AB (OR = 12.92; 95% CI 2.11-79.29; pc = 0.042), A + AB (OR = 14.67; 95% CI 2.98-72.33; pc = 0.007), and A + B + AB (OR = 9.67; 95% CI 2.02-46.24; pc = 0.035) were associated with increased risk of death in deceased cases.

Conclusions

The findings of this study suggest that group AB may be a susceptibility biomarker for COVID-19, while group A may be associated with increased risk of death.

Do Blood Group Antigens and the Red Cell Membrane Influence Human Immunodeficiency Virus Infection?

The expression of blood group antigens varies across human populations and geographical regions due to natural selection and the influence of environment factors and disease. The red cell membrane is host to numerous surface antigens which are able to influence susceptibility to disease, by acting as receptors for pathogens, or by influencing the immune response. Investigations have shown that Human Immunodeficiency Virus (HIV) can bind and gain entry into erythrocytes, and therefore it is hypothesized that blood groups could play a role in this process. The ABO blood group has been well studied. However, its role in HIV susceptibility remains controversial, while other blood group antigens, and the secretor status of individuals, have been implicated. The Duffy antigen is a chemokine receptor that is important in the inflammatory response. Those who lack this antigen, and type as Duffy null, could therefore be susceptible to HIV infection, especially if associated with neutropenia. Other antigens including those in the Rh, Lutheran and OK blood group systems have all been shown to interact with HIV. More recently, experiments show that cells which overexpress the P^k antigen appear to be protected against infection. These reports all demonstrate that red cell antigens interact and influence HIV infection. However, as the red cell membrane is complex and the pathogenesis of HIV multi-factorial, the role of blood group antigens cannot be studied in isolation.

The genetics of human ageing

The past two centuries have witnessed an unprecedented rise in human life expectancy. Sustaining longer lives with reduced periods of disability will require an understanding of the underlying mechanisms of ageing, and genetics is a powerful tool for identifying these mechanisms. Large-scale genome-wide association studies have recently identified many loci that influence key human ageing traits, including lifespan. Multi-trait loci have been linked with several age-related diseases, suggesting shared ageing influences. Mutations that drive accelerated ageing in prototypical progeria syndromes in humans point to an important role for genome maintenance and stability. Together, these different strands of genetic research are highlighting pathways for the discovery of anti-ageing interventions that may be applicable in humans.

ABO blood group distributions in multiple sclerosis patients from Basque Country; O- as a protective factor

Background

The relation between ABO/Rh groups and multiple sclerosis (MS) has been proposed in several studies, however there is a controversy about the role of these groups in the disease. Although it has been reported that some groups can be protective or risk factors, there is no consensus and discordant reports can be found in the literature.

Objectives and methodology

In this short report, we analyze the ABO/Rh distribution in a MS cohort of 265 patients and compare these frequencies with the results obtained from the Basque Blood Donors bank (17,796 individuals) of the same region.

Results and conclusions

From our data, the absence of immune antigens (A, B or Rhesus +) defined by the group O- seems to be protective in the MS group with an odds ratio of 0.49 (95% confidence interval 0.309–0.796), while the presence of Rh+ plus A or B seems to be a risk in developing multiple sclerosis.

ABO histo-blood group and risk of respiratory atopy in children: a review of published evidence

Besides their fundamental role in transfusion medicine, ABO and other histo-blood group antigens are associated with the pathogenesis of some human diseases such as malignancy and thrombosis. Reports also show a possible relationship with the risk of asthma and other forms of respiratory atopy. This paper aims to critically review the current evidence linking ABO histo-blood group with the risk of respiratory atopy in children and adults. A literature search was conducted with PubMed to gather baseline data about this relationship. The search extended to studies published within the past 45 years. First, the molecular mechanism underpinning the role of ABO antigenic system in human diseases comprises a fascinating relationship with von Willebrand factor and several pro-inflammatory and adhesion molecules. Second, specific blood group types vary with asthma phenotypes; severe asthma is associated with B phenotype, while mild and moderate asthma is associated with O and A phenotypes. Third, O phenotype has been linked to allergic rhinitis but only in males. Furthermore, asthma risk is related to O/Lewis negative/secretor phenotypes, while a significant relationship has also been established with B phenotype but not with A and O phenotypes. However, one study failed to establish a significant relationship with any of the ABO blood group antigens. In conclusion, there is no unanimity on the specific histo-blood groups linked to respiratory atopy risk, although asthma phenotypes are associated with specific blood groups. Despite the prospect that this relationship holds for the use of blood-group typing in evaluating respiratory atopy risk in children, more evidence-based studies are still required for its validation.

Human microbiota, blood group antigens, and disease

Far from being just "bugs in our guts," the microbiota interacts with the body in previously unimagined ways. Research into the genome and the microbiome has revealed that the human body and the microbiota have a long-established but only recently recognized symbiotic relationship; homeostatic balance between them regulates body function. That balance is fragile, easily disturbed, and plays a fundamental role in human health-our very survival depends on the healthy functioning of these microorganisms. Increasing rates of cardiovascular, autoimmune, and inflammatory diseases, as well as epidemics in obesity and diabetes in recent decades are believed to be explained, in part, by unintended effects on the microbiota from vaccinations, poor diets, environmental chemicals, indiscriminate antibiotic use, and "germophobia." Discovery and exploration of the brain-gut-microbiota axis have provided new insights into functional diseases of the gut, autoimmune and stress-related disorders, and the role of probiotics in treating certain affective disorders; it may even explain some aspects of autism. Research into dietary effects on the human gut microbiota led to its classification into three proposed enterotypes, but also revealed the surprising role of blood group antigens in shaping those populations. Blood group antigens have previously been associated with disease risks; their subsequent association with the microbiota may reveal mechanisms that lead to development of nutritional interventions and improved treatment modalities. Further exploration of associations between specific enteric microbes and specific metabolites will foster new dietary interventions, treatment modalities, and genetic therapies, and inevitably, their application in personalized healthcare strategies. This article is categorized under: Laboratory Methods and Technologies > Metabolomics Translational, Genomic, and Systems Medicine > Translational Medicine Physiology > Mammalian Physiology in Health and Disease.

Cardiovascular disease and ABO blood-groups in Africans. Are blood-group A individuals at higher risk of ischemic disease?: A pilot study

Background

Since the discovery of the ABO blood group system by Karl Landsteiner in 1901, several reports have suggested an important involvement of the ABO blood group system in the susceptibility to thrombosis. Assessing that non-O blood groups in particular A blood group confer a higher risk of venous and arterial thrombosis than group O.

Epidemiologic data are typically not available for all racial and ethnics groups.

The purpose of this pilot study was to identify a link between ABO blood group and ischemic disease (ID) in Africans, and to analyze whether A blood group individuals were at higher risk of ischemic disease or not.

Methods

A total of 299 medical records of patients over a three-year period admitted to the cardiology and internal medicine department of military hospital of Ouakam in Senegal were reviewed. We studied data on age, gender, past history of hypertension, diabetes, smoking, sedentarism, obesity, hyperlipidemia, use of estrogen-progestin contraceptives and blood group distribution.

In each blood group type, we evaluated the prevalence of ischemic and non-ischemic cardiovascular disease. The medical records were then stratified into two categories to evaluate incidence of ischemic disease: Group 1: Patients carrying blood-group A and Group 2: Patients carrying blood group non-A (O, AB and B).

Results

Of the 299 patients whose medical records were reviewed, 92 (30.8%) were carrying blood group A, 175 (58.5%) had blood group O, 13 (4.3%) had blood group B, and 19 (6.4%) had blood group AB.

The diagnosis of ischemic disease (ID) was higher in patients with blood group A (61.2%) than in other blood groups, and the diagnosis of non-ischemic disease (NID) was higher in patients with blood group O (73.6%) compared to other groups. In patients with blood group B or AB compared to non-B or non-AB, respectively there was no statistically significant difference in ID incidence.

Main risk factor for ID was smoking (56.5%), hypertension (18.4%) and diabetes (14.3%).

In our study, there was no statistical difference between blood group A and non-A in myocardial infarction (MI) incidence (p = 0.09, 95% CI = 0.99–2.83) but a statistically significant difference between blood group A and non-A in stroke and coronary artery disease (CAD) incidence (p < 0.0001, 95% CI = 1.80–3.37 and p < 0.0001 95% CI = 1.82–3.41 respectively) was found.

The incidence of ID in men was significantly higher in blood group A (95% CI = 2.26–4.57, p < 0.0001) compared with non-A group, while there was no statistically significant difference in women (p = 0.35). However, an overall effect was detected to be statistically significant regardless of gender (p < 0.0001).

Conclusion

Our study suggests an association between blood group A and ID in sub-Sahara Africans.

In African countries, where most of health facilities are understaffed, more rigorous studies with a larger population are needed to give a high level of evidence to confirm this association in order to establish the need to be more aggressive in risk factor control in these individuals.

Influence of ABO blood group on sports performance

BACKGROUND

Despite being a recessive trait, the O blood group is the most frequent worldwide among the ABO blood types. Since running performance has been recognized as a major driver of evolutionary advantage in humans, we planned a study to investigate whether the ABO blood group may have an influence on endurance running performance in middle-aged recreational athletes.

METHODS

The study population consisted of 52 recreational, middle-aged, Caucasian athletes (mean age: 49±13 years, body mass index, 23.4±2.3 kg/m²), regularly engaged in endurance activity. The athletes participated to a scientific event called "Run for Science" (R4S), entailing the completion of a 21.1 km (half-marathon) run under competing conditions. The ABO blood type status of the participants was provided by the local Service of Transfusion Medicine.

RESULTS

In univariate analysis, running performance was significantly associated with age and weekly training, but not with body mass index. In multiple linear regression analysis, age and weekly training remained significantly associated with running performance. The ABO blood group status was also found to be independently associated with running time, with O blood type athletes performing better than those with non-O blood groups. Overall, age, weekly training and O blood group type explained 62.2% of the total variance of running performance (age, 41.6%; training regimen, 10.5%; ABO blood group, 10.1%).

CONCLUSIONS

The results of our study show that recreational athletes with O blood group have better endurance performance compared to those with non-O blood group types. This finding may provide additional support to the putative evolutionary advantages of carrying the O blood group.

Label-free optical sensor based on red blood cells laser tweezers Raman spectroscopy analysis for ABO blood typing

The clinical significance of ABO blood typing extends beyond transfusion medicine and is demonstrated to be associated with susceptibility to various diseases, even including cancer. In this study, a home-made laser tweezers Raman spectroscopy (LTRS) system was applied to detect red blood cells (RBCs) with the aim to develop a label-free, simple and objective blood typing method for the first time. High-quality Raman spectra of RBCs in the fingerprint region of 420-1700 cm^-1 can be obtained, meanwhile exciting blood typing results can be achieved, especially with an accuracy of 100% for identifying Type AB from other blood types with the use of multivariate statistical analysis based on principal component analysis (PCA) combined with linear discriminant analysis (LDA). This primary work demonstrates that the label-free RBCs LTRS analysis in conjunction with PCA-LDA diagnostic algorithms has great potential as a biosensor for ABO blood typing.

Radiation-induced nausea and vomiting: Is ABO blood group as important as radiation and patient-related factors? An observational study

Despite the improvements in cancer screening and treatment, it still remains as one of the leading causes of mortality worldwide. Nausea and vomiting as the side effects of different cancer treatment modalities, such as radiotherapy, are multifactorial and could affect the treatment continuation and patient quality of life. Therefore, the aim of this study was to assess the possible linkage between ABO blood groups and radiation-induced nausea and vomiting (RINV), also its incidence and affecting factors.One hundred twenty-eight patients referring to Tohid hospital of Sanandaj, Iran, were selected and the patients and treatment-related factors were determined in a cross-sectional study. Patients' nausea and vomiting were recorded from the onset of treatment until 1 week after treatment accomplishment. Also, previous possible nausea and vomiting were recorded. The frequencies of nausea and vomiting and their peak time were examined during the treatment period.The association between ABO blood group and the incidence of radiotherapy-induced nausea and vomiting (RINV) were significant and it seems that A blood group patients are the most vulnerable individuals to these symptoms. The association between Rhesus antigen and the time of maximum severity of RINV may indicate that Rhesus antigen affects the time of maximum severity of RINV. The incidence of RINV was not affected by karnofsky performance status, but it was related to the severity of RINV. Furthermore, among the factors affecting the incidence of nausea and vomiting, nausea and vomiting during patient's previous chemotherapy, radiotherapy region, and background gastrointestinal disease were shown to be three important factors.In addition to familiar RINV-affecting factors, ABO blood group may play an important role and these results address the needs for further studies with larger sample size.

Replication and Characterization of Association between ABO SNPs and Red Blood Cell Traits by Meta-Analysis in Europeans

Red blood cell (RBC) traits are routinely measured in clinical practice as important markers of health. Deviations from the physiological ranges are usually a sign of disease, although variation between healthy individuals also occurs, at least partly due to genetic factors. Recent large scale genetic studies identified loci associated with one or more of these traits; further characterization of known loci and identification of new loci is necessary to better understand their role in health and disease and to identify potential molecular mechanisms. We performed meta-analysis of Metabochip association results for six RBC traits—hemoglobin concentration (Hb), hematocrit (Hct), mean corpuscular hemoglobin (MCH), mean corpuscular hemoglobin concentration (MCHC), mean corpuscular volume (MCV) and red blood cell count (RCC)—in 11 093 Europeans from seven studies of the UCL-LSHTM-Edinburgh-Bristol (UCLEB) Consortium. We identified 394 non-overlapping SNPs in five loci at genome-wide significance: 6p22.1-6p21.33 (with HFE among others), 6q23.2 (with HBS1L among others), 6q23.3 (contains no genes), 9q34.3 (only ABO gene) and 22q13.1 (with TMPRSS6 among others), replicating previous findings of association with RBC traits at these loci and extending them by imputation to 1000 Genomes. We further characterized associations between ABO SNPs and three traits: hemoglobin, hematocrit and red blood cell count, replicating them in an independent cohort. Conditional analyses indicated the independent association of each of these traits with ABO SNPs and a role for blood group O in mediating the association. The 15 most significant RBC-associated ABO SNPs were also associated with five cardiometabolic traits, with discordance in the direction of effect between groups of traits, suggesting that ABO may act through more than one mechanism to influence cardiometabolic risk.

Aging and ABO blood type influence von Willebrand factor and factor VIII levels through interrelated mechanisms

Essentials von Willebrand factor (VWF) and factor VIII (FVIII) levels are modulated by age and ABO status. The effect of aging and ABO blood type on VWF and FVIII was assessed in 207 normal individuals. Aging and ABO blood type showed combined and bidirectional influences on VWF and FVIII levels. Aging and ABO blood type influence VWF levels through both secretion and clearance mechanisms.

SUMMARY

Background The effect of aging and ABO blood type on plasma levels of von Willebrand factor (VWF) and factor VIII (FVIII) have been widely reported; however, a comprehensive analysis of their combined effect has not been performed and the mechanisms responsible for the age-related changes have not been determined. Objectives To assess the influence of aging and ABO blood type on VWF and FVIII levels, and to evaluate the contribution of VWF secretion and clearance to the age-related changes. Methods A cross-sectional observational study was performed in a cohort of 207 normal individuals, whose levels of VWF, FVIII, VWF propeptide (VWFpp), VWFpp/VWF:Ag ratio and blood type A antigen content on VWF (A-VWF) were quantified. Results Aging and ABO blood type exerted interrelated effects on VWF and FVIII plasma levels, because the age-related increase in both proteins was significantly higher in type non-O individuals (β = 0.011 vs. 0.005). This increase with age in non-O subjects drove the differences between blood types in VWF levels, as the mean difference increased from 0.13 U/mL in the young to 0.57 U/mL in the old. Moreover, A-VWF was associated with both VWF antigen (β = 0.29; 95% confidence interval [CI], 0.09, 0.50) and VWF clearance (β = -0.15; 95% CI, -0.25, -0.06). We also documented an effect of ABO blood type on VWF secretion with aging, as old individuals with blood type non-O showed higher levels of VWFpp (mean difference 0.29 U/mL). Conclusions Aging and ABO blood type have an interrelated effect on VWF and FVIII levels, where the effect of one is significantly influenced by the presence of the other.

ABO blood group system and the coronary artery disease: an updated systematic review and meta-analysis

ABO blood group system, a well-known genetic risk factor, has clinically been demonstrated to be linked with thrombotic vascular diseases. However, the relationship between ABO blood group and coronary artery disease (CAD) is still controversial. We here performed an updated meta-analysis of the related studies and tried to elucidate the potential role of ABO blood group as a risk factor for CAD. All detectable case-control and cohort studies comparing the risk of CAD in different ABO blood groups were collected for this analysis through searching PubMed, Embase, and the Cochrane Library. Ultimately, 17 studies covering 225,810 participants were included. The combined results showed that the risk of CAD was significantly higher in blood group A (OR = 1.14, 95% CI = 1.03 to 1.26, p = 0.01) and lower in blood group O (OR = 0.85, 95% CI = 0.78 to 0.94, p = 0.0008). Even when studies merely about myocardial infarction (MI) were removed, the risk of CAD was still significantly higher in blood group A (OR = 1.05, 95% CI = 1.00 to 1.10, p = 0.03) and lower in blood group O (OR = 0.89, 95% CI = 0.85 to 0.93, p < 0.00001). This updated systematic review and meta-analysis indicated that both blood group A and non-O were the risk factors of CAD.