Blood groups A and AB are associated with increased gastric cancer risk: evidence from a large genetic study and systematic review

Pathogenesis and potential reversibility of intestinal metaplasia - a milestone in gastric carcinogenesis

BACKGROUND

Non-cardia gastric cancer remains a major cause of cancer-related mortality worldwide, despite declining incidence rates in many industrialized countries. The development of intestinal-type gastric cancer occurs through a multistep process in which normal mucosa is sequentially transformed into hyperproliferative epithelium, followed by metaplastic processes leading to carcinogenesis. Chronic infection with Helicobacter pylori is the primary etiological agent that causes chronic inflammation of the gastric mucosa, induces atrophic gastritis, and can lead to intestinal metaplasia and dysplasia. Both intestinal metaplasia and dysplasia are precancerous lesions, in which gastric cancer is more likely to occur. Atrophic gastritis often improves after eradication of Helicobacter pylori; however, the occurrence of intestinal metaplasia has been traditionally regarded as "the point of no return" in the carcinogenesis sequence. Helicobacter pylori eradication heals non-atrophic chronic gastritis, may lead to regression of atrophic gastritis, and reduces the risk of gastric cancer in patients with these conditions. In this article, we discuss the pathogenesis, epigenomics, and reversibility of intestinal metaplasia and briefly touch upon potential treatment strategy.

CONCLUSIONS

Gastric intestinal metaplasia no longer appears to be an irreversible precancerous lesion. However, there are still many controversies regarding the improvement of intestinal metaplasia after Helicobacter pylori eradication.

Bacterial Infection versus Viral Infection Preference of ABO Blood Group Phenotype Patients

Several studies have established an association between the blood group type and susceptibility to infections. This study aimed to evaluate a correlation between the blood group type and the susceptibility to infection. A total of 558 patients were enrolled in this study who attended at the Althawra Hospital, Ibb City, from March to August 2018. Blood samples were analyzed for complete blood count and blood group. We observed a high frequency of infections affecting the digestive system (26.4%), while the least affected system was the urogenital system 5.9%. Patients with A blood group exhibit an increased probability to be infected by viruses than they do for bacteria (odds ratio [OR] = 1.430; 95% confidence interval [CI] = 1.005 to 2.035; P = 0.05 and OR = 0.098; 95% CI = 0.064 to 0.148; P < 0.0001, respectively). It was observed that blood group A individuals were more susceptible to infection with hepatitis B virus than were the other groups (P = 0.041; OR = 1.704, 95% CI = 1.053-2.773). The liklihood of O blood group patients experiencing urogenital infections was less than that of non-O blood group patients one third (OR = 0.353, 95% CI = 0.158-0.789; P = 0.014). This study corroborates previous findings that demonstrated that certain blood groups are more prone to infection by one agent than are patients with other blood groups.

Construction and Validation of a Gastric Cancer Diagnostic Model based on Blood Groups and Tumor Markers

Objective: The aim of this study is to explore the value of combined detection of ABO blood group and tumor markers in the diagnosis of gastric cancer. Methods: A total of 3650 gastric cancer patients treated in our center from January 2015 to December 2019, and 5822 controls were recruited, and divided into training set and validation set according to 7:3. The diagnostic and predictive model of gastric cancer was constructed by binary logistic regression method in the training set. The diagnostic value of the prediction model for gastric cancer was evaluated by calculating the prediction probability P value and drawing the Receiver operating characteristic (ROC) curve, and was verified in the validation set. Results: The Area under the curve (AUC) of the diagnosis and prediction model in the training set was 0.936 (95%CI: 0.926-0.941), the sensitivity was 81.66%, and the specificity was 98.61%. In the validation set, the AUC was 0.941 (95%CI: 0.932-0.950), the sensitivity was 82.33%, and the specificity was 99.02%. Furthermore, the diagnostic model obtained in this study had a high diagnostic value for early gastric cancer patients in the healthy population (AUC of training set, validation set and total population were 0.906, 0.920 and 0.908, respectively). Conclusions: We constructed a diagnostic model for gastric cancer including blood group and tumor markers, which has high reference value for the diagnosis of gastric cancer patients, and the model can better distinguish early gastric cancer from healthy people.

Association between ABO blood type and type I endometrial cancer: a retrospective study

This study aimed to assess the association between ABO blood type and incident of type I endometrial cancer (EC), as well as the stage and differentiation. 213 patients with type I EC and 300 healthy controls were included. As a result, the frequencies of A, B, O, and AB blood types among patients with type I EC were 51 (23.9%), 59 (27.7%), 93 (43.7%) and 10 (4.7%), respectively. There were no significant differences in age, body mass index, and other baseline covariates between groups of ABO blood types (p > .05). Logistic regression model showed that women with blood type O was more likely to develop type I EC than those with type A (odds ratio (OR): 1.66, 95% confidence interval (CI): 1.05-2.63). However, there was no significant association of ABO blood type with stage and differentiation of type I EC (p > .05). In conclusion, blood type O was the most prevalent ABO blood type among patients with type I EC and was associated with increased risk of type I EC, while ABO blood type was not significantly associated with stage or differentiation of type I EC.IMPACT STATEMENTWhat is already known on this subject? Previous studies have produced inconsistent findings on association of ABO blood type with EC. Those studies also did not explore the relationship between ABO blood type and stage or differentiation of type I EC.What the results of this study add? The present study showed that women with blood type O was more likely to develop type I EC than those with type A and there was no significant association of ABO blood type with stage or differentiation of type I EC.What the implications are of these findings for clinical practice and/or further research? Gynaecologists should pay more attention to women with blood type O, who should undergo more active EC screening.

Are ABO/Rh blood groups A risk factor for polycystic ovary syndrome?

This study goaled to evaluate the ABO/Rh blood group distribution and its relationship with clinical and biochemical factors in polycystic ovary syndrome (PCOS) patients. ABO/Rh blood group distribution of the patients and the healthy individuals were compared. In addition, the features of clinical and biochemical factors were compared according to the ABO/Rh blood groups. Two hundred and sixty-five patients were involved in the study. At the time of diagnosis, hirsutism (86%) and oligomenorrhea (80.9%) were the most prevalent symptoms. There were 166 (62.6%) patients with baseline ultrasonography results consistent with PCOS. In 111 (41.9%) patients, insulin resistance was found. ABO blood group distributions in the patient (42.6% A, 17% B, 9.4% AB, 30.9% O) and control (42% A, 16% B, 8% AB, 34% O) groups were found to be similar (P = .9). There was no difference between oligomenorrhea, hirsutism, hair loss, acne, obesity, high androgen level, insulin resistance, and ultrasound characteristics according to ABO/Rh blood groups. In this study, ABO/Rh blood group distribution in individuals with PCOS was found to be similar to healthy individuals, and it was determined that ABO/Rh blood group was not a risk factor for PCOS. In addition, no correlation was found between the clinical and biochemical characteristics of the patients at the time of diagnosis and the ABO/Rh blood group.

The Association between ABO Blood Group and the Risk of Colorectal Cancer: A Systematic Literature Review and Meta-Analysis

INTRODUCTION

Recently, studies have investigated the relationship between blood types and cancers. Contradictory results regarding the relationship between blood group type and colorectal cancer(CC) have been reported. The purpose of this study was to systematically investigate the distribution of ABO blood group frequency and evaluate its relationship with CC.

MATERIAL AND METHODS

To conduct this systematic meta-analysis, we searched PubMed, Scopus, Web of Science, and Google Scholar databases using appropriate MESH terms until July 2022. All observational studies which assessed the ABO blood group frequency distribution and the association between ABO and CC were included. The Risk of Bias Assessment tool was used to assess the quality of studies. A random model was used to estimate the odds ratio (OR). The Egger test was used to assess the publication bias.

RESULTS

Overall,14 studies (413,132 patients) were included. According to the pooled estimation, blood groups A, B, AB, and O frequency in patients with CC were 37%,18%,9%, and 31%, respectively. The OR of CC in people with the A blood group was higher than in the other groups (OR: 1.11, 95% CI:1.03,1.19, P:0.001). In contrast, the OR of CC in people with the O blood group was significantly lower than in other blood groups (OR: 0.93, 95% CI:0.83,0.97, P:0.001). No significant relationship was observed for B and AB blood groups with CC.

CONCLUSIONS

This Meta-analysis showed that blood group type A has a greater risk of developing CC, while blood group type O was associated with lower chances of CC.

Novel evidence that the ABO blood group shapes erythropoiesis and results in higher hematocrit for blood group B carriers

The ABO blood group (BG) system is of great importance for blood transfusion and organ transplantation. Since the same transcription factors (TFs) and microRNAs (miRNAs) govern the expression of ABO BG antigens and regulate erythropoiesis, we hypothesized functional connections between both processes. We found significantly higher hemoglobin and hematocrit values in BG B blood donors compared to BG A. Furthermore, we observed that erythropoiesis in BG B hematopoietic stem/progenitor cells (HSPCs) was accelerated compared to BG A HSPCs. Specifically, BG B HSPCs yielded more lineage-specific progenitors in a shorter time (B: 31.3 ± 2.2% vs. A: 22.5 ± 3.0%). Moreover, non-BG A individuals exhibited more terminally differentiated RBCs with higher enucleation rates containing more hemoglobin compared to BG A. Additionally, we detected increased levels of miRNA-215-5p and -182-5p and decreased expression of their target TFs RUNX1 and HES-1 mRNAs in erythroid BG B precursor cells compared to BG A. This highlights the important roles of these factors for the disappearance of differentiation-specific glycan antigens and the appearance of cancer-specific glycan antigens. Our work contributes to a deeper understanding of erythropoiesis gene regulatory networks and identifies its interference with BG-specific gene expression regulations particularly in diseases, where ABO BGs determine treatment susceptibility and disease progression.

Distributions and prognostic effects of ABO/Rh blood groups in patients with HER2/neu positive gastric and gastroesophageal junction cancer

BACKGROUND

The aim of study was to look at ABO/Rh blood types frequency and prognostic significance in patients with HER2/neu positive gastric cancer.

METHODS

The study was designed retrospectively. Clinicopathological characteristics, treatment approaches, and the ABO/Rh blood groups features were noted. The ABO/Rh blood types for patients and healthy donors were compared by the Chi-square method.

RESULTS

The average age was 61 years. The average survival time was 17.9 months (13.2-22.5). ABO blood types frequencies were not similar between patients (25.9% O, 6.3% AB, 57.1% A, and 10.7% B) and control group (34.9% O, 7.9% AB, 41.9% A, and 15.3% B) (P = 0.01). Patients and controls had the same Rh factor distribution (P = 0.07).

CONCLUSIONS

We showed that A blood group frequency was increased in patients with HER2/neu receptor-positive gastric cancer than in a healthy population. Also, we detected that the frequency of O blood type was decreased. ABO/Rh blood types were not linked with prognosis for overall survival.

ABO blood groups and expression of blood group antigens of epithelial ovarian cancer in Chinese women

BACKGROUND

ABO blood groups has been associated with risk of several cancers; however, the results for an association with ovarian cancer are inconsistent and little is known about the expression of histo-blood group (ABH) antigens and ABO gene in ovarian tumor tissues.

METHODS

To assess the impact of genotype-derived ABO blood types on the risk of EOC, we conducted a case-control study in 1,870 EOC and 4,829 controls. Expression of A and B antigen in 70 pairs of ovarian tumor tissues and adjacent normal tissues were detected by immunohistochemistry. Gene expression and DNA methylation profiling was conducted in ovarian tumor tissues.

RESULTS

We identified that blood group A was associated with increased risk for EOC compared to blood group O (OR = 1.18, 95% CI = 1.03-1.36, p = 0.019). Increased frequency of aberrant expression of histo-blood group antigens was observed in patients with blood group A (76.5%) compared to patients with blood group O (21.1%) and B (5.0%) by immunohistochemistry (p < 0.001). ABO gene expression was down-regulated in ovarian tumor tissues compared with paired adjacent normal tissues (p = 0.027). In addition, ABO gene expression was positively correlated with NFYB (r = 0.38, p < 0.001) and inversely correlated with DNA methylation level of four CpG sites on ABO gene (cg11879188, r = - 0.3, p = 0.002; cg22535403, r = - 0.30, p = 0.002; cg13506600, r = - 0.22, p = 0.025; cg07241568, r = - 0.21, p = 0.049) in ovarian tumor tissues.

CONCLUSION

We identified blood group A was associated with increased EOC risk in Chinese women and provided the clues of the possible molecular mechanisms of blood group A related to ovarian cancer risk.

ABO blood group distribution and risk of malignancy in patients undergoing resection for intraductal papillary mucinous neoplasm (IPMN)

BACKGROUND

The ABO blood type has been associated with risk of development of several malignancies, including pancreatic cancer. Data regarding IPMN is equivocal. To investigate this further, we analyzed the association between the ABO blood group and the presence of malignancy in a large cohort of resected IPMN and its influence in survival.

METHODS

819 patients who underwent pancreatic resection for IPMN in the Massachusetts General Hospital (MGH) and Cambridge University Hospitals NHS Foundation Trust (CUH) from January 1993 to December 2020 were identified from prospective institutional databases. Pathological characteristics and blood type were correlated.

RESULTS

The distribution of blood types A, B, AB and O was 384 (47%), 92 (11%), 44 (5%) and 299 (37%), respectively. This blood type distribution was different than the reference population of the MGH and the CUH, which is 55% non-O blood group, and 45% type O. There was a significant predominance of non-O blood types when compared with O-blood type in patients with malignant IPMN (i.e. patients with high-grade dysplasia and invasive cancer) (67% vs 33%, OR 1.31 95%CI: 0.98-1.75, p = 0.069). The association was stronger for IPMN with invasive cancer (OR 1.43 95%CI: 1.01-2.02, p = 0.039). Blood group did not influence survival.

CONCLUSION

Non-O blood type is associated with need for resection in IPMN and with presence of invasive carcinoma.

Relationship between blood type and outcomes following COVID-19 infection

Since the onset of the COVID-19 pandemic, a concentrated research effort has been undertaken to elucidate risk factors underlying viral infection, severe illness, and death. Recent studies have investigated the association between blood type and COVID-19 infection. This article aims to comprehensively review current literature and better understand the impact of blood type on viral susceptibility and outcomes.

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.

ABO Blood Groups and Its Association with Oral Cancer, Oral Potentially Malignant Disorders and Oral Submucous Fibrosis- A Systematic Review and Meta-Analysis

Objective:

The study aimed to evaluate the association between ABO blood groups and oral cancer, other potentially malignant disorders (OPMD), and oral submucous fibrosis (OSMF).

Materials and methods:

A search was conducted in Medline, Cochrane databases, Google Scholar, Scopus, Web of Science and Directory of Open Access Journals (DOAJ) for studies evaluating ABO blood groups as risk factors for oral cancer and OPMD among cases and controls. The PRISMA guidelines were followed for the meta-analysis. Participants included patients with oral cancer, and OPMD diagnosed using histopathologic investigations. Sub-group analysis was conducted to evaluate the association between blood groups and OSMF. Quality was evaluated using the Risk of Bias Assessment tool. Fixed effects model was used to assess the odds ratio for the association.

Results:

There were 1,352, 414, and 299 cases of oral cancer, OPMD, and OSMF and 11,699, 7,382 and 7,307 controls for analysis respectively. Blood group A was significantly associated with both oral cancer (Odds ratio: 1.27 [95% CI, 1.10, 1.47], P= 0.001) and OPMD (Odds ratio: 1.33 [95% CI, 1.01, 1.47], P= 0.04). No association was noted between blood group B and AB with oral cancer, OPMD, and OSMF. Blood group O was significantly associated with lower chances of oral cancer (Odds ratio: 0.81 [95% CI, 0.71, 0.93], P= 0.002).

Conclusion:

Meta-analysis suggests blood group A has a greater risk for developing oral cancer and OPMD. Blood group O was associated with lower chances of oral cancer. No association was noted between ABO blood group system with OSMF.

ABO genotypes and the risk of esophageal and gastric cancers

Background

Blood type has been associated with the risk of gastric cancer, but few studies have examined the association with esophageal squamous cell carcinoma (ESCC).

Methods

We conducted a case-control study using genotyping data of Chinese individuals, including cases of 2022 ESCC, 1189 gastric cardia adenocarcinoma, 1161 gastric noncardia adenocarcinoma, and 2696 controls. Genetic blood type was imputed using three single nucleotide polymorphisms. We used logistic regression to examine the association between blood type and the risk of each cancer.

Results

Compared to blood type O, the risk of ESCC was significantly elevated for blood type B and AB, with the highest risk for type AB (OR, 95%CI: 1.34, 1.07–1.67). Analysis of genotype suggested that the association of ESCC was from carrying the B allele. Similarly, blood type was significantly associated with gastric noncardia adenocarcinoma (P < 0.001) with risk significantly elevated in type A (1.37, 1.14–1.65) and AB (1.44, 1.10–1.89) compared to type O. Blood type was not associated with gastric cardia adenocarcinoma (P = 0.13).

Conclusions

This study provides novel insights into the association between blood type and the risk of ESCC and restricted previously observed association to only gastric noncardia cancer, providing important evidence to clarify the pattern of association and suggesting mechanisms of action.

ABO Blood Group and Risk of Pancreatic Carcinogenesis in Intraductal Papillary Mucinous Neoplasms

BACKGROUND

ABO blood group has been associated with risks of various malignancies, including pancreatic cancer. No study has evaluated the association of ABO blood group with incidence of pancreatic carcinogenesis during follow-up of patients with intraductal papillary mucinous neoplasms (IPMN).

METHODS

Among 3,164 patients diagnosed with pancreatic cysts at the University of Tokyo (Tokyo, Japan) from 1994 through 2019, we identified 1,815 patients with IPMN with available data on ABO blood group. We studied the association of ABO blood group with incidence of pancreatic carcinoma, overall and by carcinoma types [IPMN-derived carcinoma or concomitant pancreatic ductal adenocarcinoma (PDAC)]. Utilizing competing-risks proportional hazards models, we estimated subdistribution hazard ratios (SHR) for incidence of pancreatic carcinoma with adjustment for potential confounders, including cyst characteristics.

RESULTS

During 11,518 person-years of follow-up, we identified 97 patients diagnosed with pancreatic carcinoma (53 with IPMN-derived carcinoma and 44 with concomitant PDAC). Compared with patients with blood group O, patients with blood groups A, B, and AB had multivariable SHRs (95% confidence intervals) for pancreatic carcinoma of 2.25 (1.25-4.07; P = 0.007), 2.09 (1.08-4.05; P = 0.028), and 1.17 (0.43-3.19; P = 0.76), respectively. We observed no differential association of ABO blood group with pancreatic carcinoma incidence by carcinoma types.

CONCLUSIONS

In this large long-term study, patients with IPMN with blood group A or B appeared to be at higher risk of pancreatic carcinoma compared with those with blood group O.

IMPACT

ABO blood group can be a biomarker for pancreatic cancer risk among patients with IPMNs.

Association between ABO blood groups and COVID-19 infection, severity and demise: A systematic review and meta-analysis

BACKGROUND AND AIMS

The COVID-19 spreads rapidly around the world which has brought a global health crisis. The pathogen of COVID-19 is SARS-COV-2, and previous studies have proposed the relationship between ABO blood group and coronavirus. Here, we aim to delve into the association between ABO blood group and COVID-19 infection, severity and demise.

METHODS

The relevant studies were retrieved from five databases: PubMed, MedRxiv, BioRxiv,Web of Science and CNKI. Members of cases(symptomatic cases, severe cases, died cases) and controls(asymptomatic controls, non-severe controls, alive controls) were extracted from collected studies. Odds ratios (OR) and 95% confidence intervals (CI) were calculated and interpreted from extracted data. Publication bias and sensitivity analysis were also applied to confirm our discovery.

RESULTS

Overall 31,100 samples were included in the analysis. Compared to other ABO blood type, an increased odds of infecting COVID-19 among individuals with A blood group (OR: 1.249, 95%CI: 1.114-1.440, P < 0.001) and a decreased odds of infecting COVID-19 among individuals with blood group O (OR: 0.699, 95%CI: 0.635-0.770, P < 0.001) were found. Besides, individuals with blood group AB seems to link a higher risk to COVID-19 severity (OR: 2.424, 95%CI: 0.934-6.294) and demise (OR: 1.348, 95%CI: 0.507-3.583). Meantime, individuals with O blood group might had lower risk to COVID-19 severity (OR: 0.748, 95%CI: 0.556-1.007), and individuals with B blood group were likely to relate a lower risk to COVID-19 demise.

CONCLUSIONS

The current meta-analysis suggest that blood type A might be more susceptible to infect COVID-19 while blood type O might be less susceptible to infect COVID-19; there were no correlation between ABO blood group and severity or demise of COVID-19. However, more investigation and research are warranted to clarify the relationship between COVID-19 and ABO blood type.

Associations between birth season and the anatomic subsites of gastric cancer in Beijing, China

Birth season is an important risk factor for several cancers; for example, anatomic subsite risk factors for gastric cancer differ substantially by when patients were born. In this population-based retrospective study, we explored the relationship between birth season and gastric cancer of different anatomical sites, focusing on gastric cancer patients who were registered at the Beijing Institute for Cancer Research from 2003 to 2012. In total, 19,668 patients were divided into three groups according to the anatomical site of the primary lesion: cardia (n = 3911), noncardia (n = 5383) and unknown (n = 10,374). The 5383 patients in the noncardia group were further subdivided into the following subgroups: fundus (n = 455), corpus (n = 902), greater curvature (n = 110), lesser curvature (n = 512), antrum (n = 2635), pylorus (n = 106) and overlapping (n = 663). Finally, all gastric cancer cases, the three major groups, and the seven noncardia subgroups were, respectively, compared with inpatients from the Dongzhimen Hospital of Beijing from 2003 to 2013. A logistic regression method with sex and age as control factors was used to evaluate the relationship between birth season and gastric cancer with the level for statistical significance set at P < .05. Taking winter as the reference season, we found people born in summer had a lower probability of developing gastric cancer (summer: odds ratio [OR] = 0.925, 95% confidence interval [CI] = 0.875-0.978, P = .006). Among the three groups, the noncardia group had the lower probability of birth season being spring or summer (spring: OR = 0.917, 95% CI = 0.843-0.997, P = .042; summer: OR = 0.883, 95% CI = 0.810-0.962, P = .004), but the cardia and unknown anatomical groups showed no statistical significance for season of birth (P > .05). Among the seven subgroups, those born in summer were less likely to develop gastric cancer in the antrum and lesser curvature than those born in winter (antrum: OR = 0.861, 95% CI = 0.766-0.968, P = .012; lesser curvature: OR = 0.746, 95% CI = 0.579-0.961, P = .023); the other subgroups showed no significant differences by season of birth (P > .05). This study demonstrated that gastric cancer is related to birth season. For people born in summer, the risk of developing gastric cancer was comparatively lower than for people born in winter. Seasonal differences in immune function and maternal nutrition status during pregnancy may explain these findings; however, further large-scale prospective studies will be required to validate these findings.

[Blood group and human diseases (review of literature).]

AB0 blood group antigens were discovered over a century ago; however, it is still important to study their role in development of various pathological conditions. Today it is known that antigenic determinants of this blood group are present not only on erythrocyte membrane but also on other cells and tissues: platelets, gastrointestinal epithelium and salivary glands, respiratory system cells. In the last decade, a large number of studies have appeared to reveal the relationship between a specific disease and blood group type, meta-analyses have been published. Previously, the authors have studied the metabolic status, cell composition and coagulation profile of clinically healthy individuals for more than on 180,000 donations, that allowed to identify groupspecific features for each blood group. This review presents generalized data on the association of such pathological conditions as coronary heart disease, thromboembolic complications, tumors of various localizations, inflammatory and destructive oral diseases, psychiatric and some infectious diseases with the presence or absence of antigenic determinants A and B. Carriers of blood group 0 (I) are generally more resistant to diseases, with the exception of H.pylori-associated gastrointestinal diseases. Carriers of «antigenic» blood groups A (II), B (III), AB (IV) are more susceptible to development of infectious, cardiovascular and cancer diseases. The presented data demonstrate clinical significance of the definition of group typing not only for selection of blood and its components during transfusion and transplantation, but also for diagnostics, determination of risk group and tactics for treatment patients with different nosologies.