Relationships between the ABO blood group SNP rs505922 and breast cancer phenotypes: a genotype-phenotype correlation study

Non-O-blood types associated with higher risk of high-grade atrioventricular block

Introduction

The non-O phenotype of the ABO genotype has been linked with an increased risk of cardiovascular disease. Atrioventricular (AV) block (AVB) is defined as retardation or cessation in the route of an electrical impulse passing from the atria to the ventricles because of an anatomical or functional disruption in the conduction system. We aimed to interpret the association between blood group status and high-grade atrioventricular block (HAVB).

Material and methods

This study was implemented as a retrospective review of the recorded data of patients diagnosed with high-grade AV block and a control group. The study population consisted of 640 patients with HAVB and 570 control subjects.

Results

Presence of non-O blood group (p < 0.001) was significantly more prevalent in HAVB patients than in the control subjects. Blood group type was the sole independent predictor of HAVB in multiple regression analysis (p < 0.001, OR = 1.35, 95% CI: 1.08–1.57). Also, third-degree AVB had a higher incidence in the non-O blood subgroup and also non-O blood group was a predictor of third-degree AVB (p < 0.001, OR = 1.39, 95% CI: 1.13–1.69). The incidence of HAVB did not distinguish between the two Rh (D) groups. Rh (D) status did not have an impact on HAVB.

Conclusions

This is the first study that has evaluated the potential relationship between HAVB and ABO blood groups. The main finding of this report is that patients with non-O blood group types have a higher risk for development of HAVB compared with O blood group patients.

Potential Association of IL1B Polymorphism With Iron Deficiency Risk in Childhood Helicobacter pylori Infection

OBJECTIVE

Helicobacter pylori infection occurs predominantly in childhood. Host immune response gene polymorphism is reported to affect the susceptibility to H pylori infection and the outcome of H pylori-related gastric cancer. Not all H pylori-infected patients, however, exhibit iron deficiency (ID). The relationship between host genetic polymorphisms and ID mediated by H pylori infection is not well understood.

METHODS

Subjects (n = 644) from the general population of age 10 to 18 years were divided into 2 groups based on serology testing for anti-H pylori IgG: seropositive study group; and seronegative control group. Five single nucleotide polymorphisms (SNPs) in IL1B (rs1143627 and rs16944), IL8 (rs4073), IL10 (rs1800896), and ABO (rs505922), were genotyped and the iron status of the 2 groups was compared.

RESULTS

The seroprevalence rate for H pylori was 10.7% in this study. Infected subjects were significantly older and had lower serum iron levels than uninfected subjects (P = 0.0195 and 0.0059, respectively). Multivariate analysis revealed a significantly higher frequency of the T allele of rs505922 (odds ratio [OR] = 6.128; P < 0.001) and lower frequency of the T allele of rs1143627 (OR = 0.846; P = 0.014) in seropositive subjects. Among 59 seropositive subjects, the T allele frequency of rs1143627 was significantly higher in those with ID (OR = 3.156; P = 0.043), compared with those without ID.

CONCLUSIONS

ABO (rs505922) and IL1B (rs1143627) may affect H pylori infection susceptibility, and IL1B (rs1143627) may also influence ID risk in infected children.

The role of the histoblood ABO group in cancer

Since the first link between blood type and cancer was described in 1953, numerous studies have sought to determine whether the histoblood ABO group is associated with tumorigenesis. In 2009, the first significant association between a SNP located within the ABO glycosyltransferase gene and increased risk of pancreatic cancer was reported. Here, we describe the history and possible functions of the histoblood ABO group and then provide evidence for a role of blood group antigens in the most common cancer types worldwide using both blood type and SNP data. We also explore whether confusion regarding the role of blood type in cancer risk may be attributable to heterogeneity within tumor types.

Lay abstract: ABO encodes the protein responsible for defining blood groups as A, B, AB or O. Despite over a century of investigation, it is not well known whether the blood group antigens have a function or if they contribute to human health. Over the last 60 years, associations between blood type and cancer risk have been reported, although the data have often been conflicting. To better understand the possible role of the ABO blood group in tumorigenesis, we review the data for the most common tumor types worldwide.

Innate Susceptibility to Norovirus Infections Influenced by FUT2 Genotype in a United States Pediatric Population

BACKGROUND

Norovirus is a leading cause of acute gastroenteritis (AGE). Noroviruses bind to gut histo-blood group antigens (HBGAs), but only 70%-80% of individuals have a functional copy of the FUT2 ("secretor") gene required for gut HBGA expression; these individuals are known as "secretors." Susceptibility to some noroviruses depends on FUT2 secretor status, but the population impact of this association is not established.

METHODS

From December 2011 to November 2012, active AGE surveillance was performed at 6 geographically diverse pediatric sites in the United States. Case patients aged <5 years were recruited from emergency departments and inpatient units; age-matched healthy controls were recruited at well-child visits. Salivary DNA was collected to determine secretor status and genetic ancestry. Stool was tested for norovirus by real-time reverse transcription polymerase chain reaction. Norovirus genotype was then determined by sequencing.

RESULTS

Norovirus was detected in 302 of 1465 (21%) AGE cases and 52 of 826 (6%) healthy controls. Norovirus AGE cases were 2.8-fold more likely than norovirus-negative controls to be secretors (P < .001) in a logistic regression model adjusted for ancestry, age, site, and health insurance. Secretors comprised all 155 cases and 21 asymptomatic infections with the most prevalent norovirus, GII.4. Control children of Meso-American ancestry were more likely than children of European or African ancestry to be secretors (96% vs 74%; P < .001).

CONCLUSIONS

FUT2 status is associated with norovirus infection and varies by ancestry. GII.4 norovirus exclusively infected secretors. These findings are important to norovirus vaccine trials and design of agents that may block norovirus-HBGA binding.

Identification of six new susceptibility loci for invasive epithelial ovarian cancer

Genome-wide association studies (GWAS) have identified 12 epithelial ovarian cancer (EOC) susceptibility alleles. The pattern of association at these loci is consistent in BRCA1 and BRCA2 mutation carriers who are at high risk of EOC. After imputation to 1000 Genomes Project data, we assessed associations of 11 million genetic variants with EOC risk from 15,437 cases unselected for family history and 30,845 controls and from 15,252 BRCA1 mutation carriers and 8,211 BRCA2 mutation carriers (3,096 with ovarian cancer), and we combined the results in a meta-analysis. This new study design yielded increased statistical power, leading to the discovery of six new EOC susceptibility loci. Variants at 1p36 (nearest gene, WNT4), 4q26 (SYNPO2), 9q34.2 (ABO) and 17q11.2 (ATAD5) were associated with EOC risk, and at 1p34.3 (RSPO1) and 6p22.1 (GPX6) variants were specifically associated with the serous EOC subtype, all with P < 5 × 10(-8). Incorporating these variants into risk assessment tools will improve clinical risk predictions for BRCA1 and BRCA2 mutation carriers.