Clinical significance of the fucosyltransferase 2 (FUT2) secretor status in children hospitalized with acute gastroenteritis in Taiwan

Association of fucosyltransferase 2 gene polymorphism with the susceptibility to norovirus infection in Han Chinese population

Fucosyltransferase 2 (FUT2) gene, which regulates the formation of Histoblood group antigens, could determine the human susceptibility to norovirus. This study aimed to investigate the correlation between FUT2 gene polymorphism and susceptibility to norovirus gastroenteritis in Han Chinese population. A total of 212 children patients with acute gastroenteritis were enrolled. The stool and serum samples were collected respectively. We used the qPCR method to detect the norovirus infection status from the stool samples, and we used serum samples to detect the FUT2 polymorphism. A case-control study was conducted to investigate the three common SNPs polymorphisms (rs281377, rs1047781, and rs601338) of FUT2 gene with sanger sequencing method. The results indicated that the homozygous genotypes and mutant allele of rs1047781 (A385T) would downgrade the risk of norovirus gastroenteritis in Chinese Han population (AA vs. TT, odds ratio [OR] = 0.098, 95% confidence interval [CI] = 0.026-0.370, p = 0.001; AA + AT vs. TT, OR = 0.118. 95% CI = 0.033-0.424, p = 0.001; A vs. T, OR = 0.528, 95% CI = 0.351-0.974, p = 0.002). There were no significant difference of rs281377 (C357T) and rs601338 (G428A) polymorphisms between norovirus positive and norovirus negative groups (p > 0.05). The haplotype T-T-G was less susceptible (OR = 0.49, 95% CI = 0.31-0.79, p = 0.0034) to norovirus infection compared to other haplotypes. Our results investigated the relationship between the FUT2 gene polymorphisms and norovirus susceptibility in Han Chinese population, and firstly revealed that children with homozygous genotypes and mutant alleles of FUT2 rs1047781 (A385T) were less susceptible to norovirus gastroenteritis.

Chemo-sensory loss and FUT2 gene in COVID-19 infected Iraqi dentists

OBJECTIVE

Aim: To find any association between specific ABO blood groups and FUT2 secretory status and COVID-19 in a sample of Iraqi dentists.

PATIENTS AND METHODS

Materials and Methods: For each participant, a questionnaire including demography, COVID-19 status, blood grouping, and RH factor, with chemo-sensitive symptoms was recorded. The saliva samples were collected and DNA was extracted from leukocytes. Sequencing of molecular detection of the FUT2 gene by real-time PCR and the data was done, whilst drawing the phylogenetic tree.

RESULTS

Results: Out of 133, most of the dentists were female 61%, most were just under 35 years of age. The most participants in this study were predominantly with blood group O (40%), followed by B, A, and AB, with (90%) of them were RH+. All blood grouping and RH factor were high significantly associated with COVID-19 infection and its frequency (p<0.001). A significant association between smell dysfunction and infected blood group A and RH+ (p =0.044, 0.038) while taste dysfunction was negatively and significantly correlated with AB group (r=-0.73; p=0.008). The FUT2 secretor showed a significant association with COVID-19 infection and frequency. The majority of COVID-19-infected participants experienced a significant loss of both smell and taste with fast recovery within 2 weeks.

CONCLUSION

Conclusions: The COVID-19 infection susceptibility and reinfection are associated with FUT2 secretory status and greatly associated to olfactory and gustatory sense loss.

The Role of Host Glycobiology and Gut Microbiota in Rotavirus and Norovirus Infection, an Update

Rotavirus (RV) and norovirus (NoV) are the leading causes of acute gastroenteritis (AGE) worldwide. Several studies have demonstrated that histo-blood group antigens (HBGAs) have a role in NoV and RV infections since their presence on the gut epithelial surfaces is essential for the susceptibility to many NoV and RV genotypes. Polymorphisms in genes that code for enzymes required for HBGAs synthesis lead to secretor or non-secretor and Lewis positive or Lewis negative individuals. While secretor individuals appear to be more susceptible to RV infections, regarding NoVs infections, there are too many discrepancies that prevent the ability to draw conclusions. A second factor that influences enteric viral infections is the gut microbiota of the host. In vitro and animal studies have determined that the gut microbiota limits, but in some cases enhances enteric viral infection. The ways that microbiota can enhance NoV or RV infection include virion stabilization and promotion of virus attachment to host cells, whereas experiments with microbiota-depleted and germ-free animals point to immunoregulation as the mechanism by which the microbiota restrict infection. Human trials with live, attenuated RV vaccines and analysis of the microbiota in responder and non-responder individuals also allowed the identification of bacterial taxa linked to vaccine efficacy. As more information is gained on the complex relationships that are established between the host (glycobiology and immune system), the gut microbiota and intestinal viruses, new avenues will open for the development of novel anti-NoV and anti-RV therapies.

Association of fucosyltransferase 2 gene with norovirus infection: A systematic review and meta-analysis

BACKGROUND

Norovirus is a leading cause of viral gastroenteritis outbreaks worldwide. Histo-blood group antigens (HBGAs) are important host attachment factors in susceptibility to norovirus. In this study, the association of FUT2 gene, which participates in the biosynthesis of HBGAs, with norovirus infection has been investigated.

METHODS

All relevant studies on the associations of FUT2 gene with norovirus were retrieved from PubMed, Web of Science, Embase, and Cochrane Library databases. Odds ratios (ORs) and 95% confidence interval (CI) were used to analyze the extracted data. I2 statistic, sensitivity analysis and publication bias analysis were used to confirm the findings. Subgroup analyses were performed for races, genotypes, development degree of the countries, publication years, age and setting when heterogeneity was recorded.

RESULTS

Twenty studies including 4066 participants were included for the meta-analysis. This analysis showed that there is a significant association between FUT2 gene and norovirus infection (OR = 3.02, 95%CI = 2.00-4.55, P < 0.001). Additionally, the ORs of norovirus infection among Chinese (OR = 4.49, 95%CI = 2.37-8.50, P < 0.001) were higher than those among Caucasian (OR = 3.23, 95%CI = 2.20-4.74, P < 0.001).

CONCLUSIONS

The meta-analysis suggested that FUT2 gene is associated with susceptibility to norovirus infection.

Serological Humoral Immunity Following Natural Infection of Children with High Burden Gastrointestinal Viruses

Acute gastroenteritis (AGE) is a major cause of morbidity and mortality worldwide, resulting in an estimated 440,571 deaths of children under age 5 annually. Rotavirus, norovirus, and sapovirus are leading causes of childhood AGE. A successful rotavirus vaccine has reduced rotavirus hospitalizations by more than 50%. Using rotavirus as a guide, elucidating the determinants, breath, and duration of serological antibody immunity to AGE viruses, as well as host genetic factors that define susceptibility is essential for informing development of future vaccines and improving current vaccine candidates. Here, we summarize the current knowledge of disease burden and serological antibody immunity following natural infection to inform further vaccine development for these three high-burden viruses.

Global prevalence and genotype distribution of norovirus infection in children with gastroenteritis: A meta-analysis on 6 years of research from 2015 to 2020

In the post rotavirus vaccine era, norovirus (NoV) plays an increasingly important role in epidemic and sporadic gastroenteritis among children. This study was designed to provide an updated meta-analytic review of the prevalence of NoV among paediatric patients with gastroenteritis and to clarify the relationship between NoV infection and gastroenteritis. Systematic searches of the literature for potentially relevant studies were carried out from 1 January 2015 to 29 May 2020. The inverse variance method was chosen for weighting of the studies, and the random-effects model was used to analyse data. To determine the association between NoV infection and gastroenteritis in children, pooled odds ratio (OR) and its 95% confidence interval (CI) were computed for case-control studies. The pooled prevalence of NoV infection among 12,0531 children with gastroenteritis from 45 countries across the world was 17.7% (95% CI: 16.3%-19.2%). There were 28 studies with a case-control design, and the pooled prevalence of NoV infection among 11,954 control subjects was 6.7% (95% CI: 5.1%-8.8%). The pooled OR of the association of NoV infection and gastroenteritis was 2.7 (95% CI: 2.2-3.4). The most common NoV genotypes were GII.4 (59.3%) and GII.3 (14.9%). The highest frequency of NoV was found in the age group below 1 year. Our findings indicated a substantial burden of gastroenteritis caused by NoV globally, with GII.4 and GII.3 the major genotypes responsible for the majority of NoV-associated gastroenteritis cases among children. Younger age and male sex can be considered risk factors for NoV-associated gastroenteritis among children.