ABO Genotyping Research Articles

Identification of a novel variant c.761C>T on ABO*B.01 gene in ABO glycosyltransferases associated with Bweak phenotype.

ABO antigens are produced from H antigen by the activity of glycosyltransferase enzyme encoded by the ABO gene. Variants in the ABO gene can produce a weak ABO phenotype. In this study, we identify a novel ABO*BW allele and investigate the underlying mechanism leading to the Bweak phenotype. The ABO phenotype and genotype of the sample were determined using serological and direct DNA sequencing methods. We assessed the impact of the novel variant by three-dimensional modelling to predict protein stability changes (ΔΔG), and carried out an in vitro expression assay. The total glycosyltransferase transfer capacity in the supernatant of transfected cells was also examined. Serological analysis confirmed the Bweak phenotype in the subject, and gene sequencing identified a novel variant c.761C>T (p.A254V) on the ABO*B.01 allele, resulting in a BW-var/O.01.02 genotype. In silico analysis suggested that the p.A254V variant on the B allele may reduce the stability of glycosyltransferase B (GTB), as indicated by the ΔΔG values. In vitro expression studies showed that the variant p.A254V impaired H to B antigen conversion, although it did not affect the expression of GTB. We identified a novel BW allele and demonstrated that the variant c.761C>T (p.A254V) can cause the Bweak phenotype by reducing the stability of GTB.

A Pedigree Investigation of H-antigen Deletion Caused by Mutation of 658 C to T in the FUT1 Gene.

H-antigen deletion is often caused by FUT1 gene mutation, which is a very rare blood group. In this case, the H-antigen phenotype, FUT1, FUT2 sequences, and family genetic investigation of a 26-year-old patient (proband) and her three family members were studied. The results showed that the proband and little her brother were H-deficient phenotype, their ABO genotype of both was A/O1, her father was A/B, and her mother was O1/O1. The proband and her little brother's FUT1 phenotype were both h3|h3, with a homozygous mutation 658C > T in their FUT1 gene, and the FUT1 phenotype of their parents' were H|h3, with a heterozygous mutation (658C > T) in their FUT1 gene. The result of whole gene sequencing showed that the father of the proband had a deletion of CHR19.49,255,178-49,257,177 in the FUT1 gene (hg19 was used as the reference). The results of the family investigation showed that the mutation of site 658 in the FUT1 gene between offspring and parents was consistent with Mendelian inheritance law.

Considerations on ABO Genotyping Results: Lessons from ABO*AW.10 Allele Cases

Considerations on ABO Genotyping Results: Lessons from <i>ABO*AW.10</i> Allele Cases

Clinical Application of ABO Genotyping: 5-Year Experience from a Single Tertiary Care Center in Korea

Clinical Application of ABO Genotyping: 5-Year Experience from a Single Tertiary Care Center in Korea

Phenotype, allele and genotype frequency distribution of ABO and Rh(D) blood group among blood donors attending regional blood transfusion centre in Delhi, India.

The ABO and Rh blood group phenotypes, alleles, and genotype frequencies have many biological and medical implications. The frequency differs broadly according to races, geographical borders and ethnicity, even within the same region. This study was designed to determine the frequency of ABO and Rh blood groups among blood donors attending the regional blood transfusion centre in Delhi. The gel card method was used to determine the ABO and Rh(D) blood groups of donors who donated blood between January 1, 2020, and June 30, 2022. The assumption of Hardy-Weinberg equilibrium was used to determine allele and genotype frequencies of blood donors. A total of 16,925 blood units were donated during the study period. Donors phenotype frequencies of ABO were as follows: 'A' (23.88%), 'B' (37.38%), 'AB' (9.97%) and 'O '(29.27%). Rh(D)+Ve (D) were (94.9%) and Rh(D)-Ve (d) were (5.01%), which follow an order of B > O > A > AB and Rh-D > d for Rh. Donors ABO and Rh (D) allele frequencies were IA-0.183, IB-0.277, IO-0.541 and ID-0.776, Id-0.224 respectively. Allele frequencies follow an order of IO > IB > IA and Rh- ID > Id. Donors ABO genotype frequencies were AA-0.0333, AO-0.198, BB-0.0768, BO-0.30, AB-0.101, OO-0.293 and Rh(D) genotype frequencies were DD-0.602, Dd-0.347, dd-0.0501. Genotype frequencies follow an order of BO > OO > AO > AB > BB > AA and DD > Dd > dd. Among our donors, which were mostly from northern India, the ABO and Rh(D) blood groups have the highest proportion of ABO-B and Rh(D)+Ve and the lowest proportion of ABO-AB and Rh(D)-Ve, with a stable order of B > O > A > AB and D > d for phenotype, IO > IB > IA and ID > Id for allele and BO > OO > AO > AB > BB > AA and DD > Dd > dd for genotype.

Rapid Identification of Seven Common ABO Alleles by Two-Dimensional Polymerase Chain Reaction Technology

Introduction: The molecular biology detection technology of the human ABO blood group system makes up for the limitations in many aspects compared with conventional serological typing technology. This study aimed to establish a new method to identify seven common ABO alleles (ABO*A1.01, ABO*A1.02, ABO*A2.01, ABO*B.01, ABO*O.01.01, ABO*O.01.02, and ABO*O.02.01) by two-dimensional polymerase chain reaction (2D PCR). 2D PCR can identify multiple target genes in a closed test tube by labeling specific primers with tags homologous to the sequence of fluorescently labeled probes, and melting curve analysis is performed after the fluorescent probes are hybridized with tag complementary sequences in PCR-specific products. In this study, 2D PCR and PCR sequence-specific primer (PCR-SSP) were combined to discriminate different alleles in a single reaction, which has the characteristics of high throughput, and compared with other typing techniques; the typing results can be obtained without additional operations. Methods: The ABO*A1.01 allele genetic sequence was used as the reference sequence. The specific sense and antisense primers for seven common ABO alleles were designed on exons 6 and 7 according to the principle of 2D PCR and PCR-SSP. Single nucleotide polymorphism sites for identifying seven alleles were detected in FAM and HEX channels, respectively. Two hundred sixty DNA samples were enrolled for rapid ABO genotyping by 2D PCR, and 95 of them were selected for Sanger sequencing. The Kappa test was used to analyze the agreement of the methodologies. Results: These 7 alleles each had four characteristic melting valleys at different single nucleotide polymorphism loci. A total of 15 genotypes were detected, including ABO*A1.01/A1.02, ABO*A1.01/O.01.01, ABO*A1.01/O.01.02, ABO*A1.02/A1.02, ABO*A1.02/O.01.01, ABO*A1.02/O.01.02, ABO*B.01/B.01, ABO*B.01/O.01.01, ABO*B.01/O.01.02, ABO*O.01.01/O.01.01, ABO*O.01.01/O.01.02, ABO*O.01.02/O.01.02, ABO*A1.01/B.01, ABO*A1.02/B.01, and ABO*B.01/O.01. v (containing a rare ABO*O allele, based on the sequencing results). The Kappa test showed completely consistent results for 2D PCR and Sanger sequencing (Kappa = 1). Conclusion: The 2D PCR technique could be used for molecular typing of the ABO blood group, which was efficient, rapid, accurate, and economical.

Serological Characteristics of Subtype A Caused by New A Allele Mutation and a Family Survey

In this study, the results of forward and reverse blood typing of a male patient diagnosed as bronchiectasis were inconsistent, which were type O and type A respectively. Multiple experiments including genotyping and sequencing and family investigation were carried out to determine the subtype of ABO blood group and explore the serological characteristics of this subtype. Standard serological techniques were used to conduct forward and reverse typing, reverse blood typing enhancement test, H antigen identification, absorption-elution test, salivary blood group substances test, and PCR-SSP method for ABO genotyping and exon 6 and 7 sequencing. The proband's blood group was type O by forward typing, but antigen A could be detected by absorption-elution test, anti-A1 could be detected by reverse blood typing enhancement test, it was found that there was substance H but no substance A in saliva, and the serological characteristics were consistent with Ael subtype. Gene sequencing analysis showed that there was a c.625T>G base substitution on the basis of A102, which had never been reported before. Family survey showed that c.625T>G base substitution appeared in three generations of the family. In this study, a new subtype A with Ael serological characteristics caused by c.625T>G mutation was identified. c.625T>G base substitution results in the weakening of A antigen, and this mutation can be stably passed down to future generations.

Haplotype sequence collection of ABO blood group alleles by long-read sequencing reveals putative A1-diagnostic variants.

In the era of blood group genomics, reference collections of complete and fully resolved blood group gene alleles have gained high importance. For most blood groups, however, such collections are currently lacking, as resolving full-length gene sequences as haplotypes (ie, separated maternal/paternal origin) remains exceedingly difficult with both Sanger and short-read next-generation sequencing. Using the latest third-generation long-read sequencing, we generated a collection of fully resolved sequences for all 6 main ABO allele groups: ABO∗A1/A2/B/O.01.01/O.01.02/O.02. We selected 77 samples from an ABO genotype data set (n= 25 200) of serologically typed Swiss blood donors. The entire ABO gene was amplified in 2 overlapping long-range polymerase chain reactions (covering ∼23.6 kb) and sequenced by long-read Oxford Nanopore sequencing. For quality validation, 2 samples per ABO group were resequenced using Illumina and Pacific Biosciences technology. All 154 full-length ABO sequences were resolved as haplotypes. We observed novel, distinct sequence patterns for each ABO group. Most genetic diversity was found between, not within, ABO groups. Phylogenetic tree and haplotype network analyses highlighted distinct clades of each ABO group. Strikingly, our data uncovered 4 genetic variants putatively specific for ABO∗A1, for which direct diagnostic targets are currently lacking. We validated A1-diagnostic potential using whole-genome data (n= 4872) of a multiethnic cohort. Overall, our sequencing strategy proved powerful for producing high-quality ABO haplotypes and holds promise for generating similar collections for other blood groups. The publicly available collection of 154 haplotypes will serve as a valuable resource for molecular analyses of ABO, as well as studies about the function and evolutionary history of ABO.

Identification of two novel FUT1 mutations in people with Bombay phenotype from Iran

Background and purposeBombay and Para-Bombay phenotypes are characterized by FUT1 gene mutation and lack of H antigen expression in red blood cells. ABH antigens are not present in the body secretions of Bombay individuals, while they are expressed in the secretions of para-Bombay. The aim of this study was to investigate the molecular basis of FUT1 and FUT2 genes in Iranians with the Bombay or Para-Bombay phenotype. Materials and MethodsABO phenotype analysis and routine serological tests were performed on 11 people with Bombay and Para-Bombay phenotypes. The coding regions of FUT1 and FUT2 genes were amplified by PCR followed by sequencing. The ABO genotypes were also determined by sequencing exons 6 and 7 of the ABO gene. Results: Serological investigations confirmed the Bombay phenotype in 8 samples and the Para-Bombay phenotype in 3 samples. Family members with the Bombay phenotype had the classic c 0.725 T > G mutation in the FUT1 gene, accompanied by deletion of the FUT2 gene. Other samples had c.653 A>G, c 0.661 C>T, c 0.652 C>G, and c.722 A>C mutations in the FUT1 while FUT2 was silenced by c 0.461 G>A. Conclusion: In this research, we identified two novel mutations in the FUT1 gene in individuals with the Bombay phenotype. This and previous works confirm the variety of FUT1 mutations.

ABO Genotyping finds more A2 to B kidney transplant opportunities than lectin-based subtyping

ABO compatibility is important for kidney transplantation, with longer waitlist times for blood group B kidney transplant candidates. However, kidneys from non-A1 (eg, A2) subtype donors, which express less A antigen, can be safely transplanted into group B recipients. ABO subtyping is routinely performed using anti-A1 lectin, but DNA-based genotyping is also possible. Here, we compare lectin and genotyping testing. Lectin and genotype subtyping was performed on 554 group A deceased donor samples at 2 transplant laboratories. The findings were supported by 2 additional data sets of 210 group A living kidney donors and 124 samples with unclear lectin testing sent to a reference laboratory. In deceased donors, genotyping found 65% more A2 donors than lectin testing, most with weak lectin reactivity, a finding supported in living donors and samples sent for reference testing. DNA sequencing and flow cytometry showed that the discordances were because of several factors, including transfusion, small variability in A antigen levels, and rare ABO∗A2.06 and ABO∗A2.16 sequences. Although lectin testing is the current standard for transplantation subtyping, genotyping is accurate and could increase A2 kidney transplant opportunities for group B candidates, a difference that should reduce group B wait times and improve transplant equity.

Evaluation of Single Nucleotide Variants in Intron 1 of the ABO Gene as Diagnostic Markers for the A1 Blood Group

Introduction: The molecular diagnosis of the A₁ blood group is based on the exclusion of ABO gene variants causing blood groups A₂, B, or O. A specific genetic marker for the A₁ blood group is still missing. Recently, long-read ABO sequencing revealed four sequence variations in intron 1 as promising markers for the ABO*A1 allele. Here, we evaluated the diagnostic values of the 4 variants in blood donors with regular and weak A phenotypes and genotypes. Methods: ABO phenotype data (A, B, AB, or O) were taken from the blood donor files. The ABO genotypes (low resolution) were known from a previous study and included the variants c.261delG, c.802G>A, c.803G>C, and c.1061delC. ABO variant alleles (ABO*AW.06,*AW.08,*AW.09,*AW.13, *AW.30, and *A3.02) were identified in weak A donors by sequencing the ABO exons before. For genotyping of the ABO intron 1 variants rs532436, rs1554760445, rs507666, and rs2519093, we applied TaqMan assays with endpoint fluorescence detection according to a standard protocol. Genotypes of the variants were compared with the ABO phenotype and genotype. Evaluation of diagnostic performance included sensitivity, specificity, positive (PPV), and negative predictive value (NPV). Results: In 1,330 blood donors with regular ABO phenotypes and genotypes, the intron 1 variants were significantly associated with the proposed A₁ blood group. In 15 donors, we found discrepancies to the genotype of at least one of the 4 variants. For the diagnosis of the ABO*A1 allele, the variants showed 98.79–99.48% sensitivity, 99.66–99.81% specificity, 98.80–99.31% PPV, and 99.66–99.86% NPV. Regarding the A phenotype, the diagnostic values were 99.02–99.41% sensitivity, 99.63–99.76% specificity, 99.41–99.61% PPV, and 99.39–99.63% NPV. The *A1 marker allele of all intron 1 variants was also associated with the *AW.06, *AW.13, and *AW.30 variants. Samples with *AW.08, *AW.09, and *A3.02 variants lacked this association. Conclusion: The ABO intron 1 variants revealed significant association with the ABO*A1 allele and the A phenotype. However, the intron 1 genotype does not exclude variant alleles causing weak A phenotypes. With the introduction of reliable tag, single nucleotide variants for the A₁, A₂, B, and O blood groups and the genotyping instead of phenotyping of the ABO blood group are getting more feasible on a routine basis.

ABO discrepancy due to the para-Bombay phenotype: a case report

In this study, we aimed to determine and analyze the genetic differences of the FUT1 and FUT2 genes within an individual exhibiting the Para-Bombay phenotype. Standard serological tests were conducted to analyze the ABO phenotype. The amplification of FUT1 and FUT2 genes was conducted by polymerase chain reaction and amplicons were sequenced. The determination of the ABO genotype was conducted by sequencing exons 1 to 7 of the ABO gene. The Lewis phenotype was defined as Le(a−b+); Despite this, red blood cells (RBCs) did not show signs of A, B and H antigens using the serological method utilized in this study. However, Analyses of sequencing and cloning demonstrated the existence of a FUT1 mutation at position c.658C&gt;T and an inactive allele FUT1*01N.06 (c.551_552delAG). Genetic testing for ABO blood types was subsequently determined to be ABO*B.01/ABO*B.01 (c.297A&gt;G; c.526C&gt;G; c.657C&gt;T; c.703G&gt;A; c.796C&gt;A; c.803G&gt;C; c.930G&gt;A). Heterozygosity for indel and missense mutation within the coding region of FUT1 are likely to be responsible for development of the Para-Bombay phenotype.

Association of the BB genotype of the ABO gene with the risk of acute myocardial infarction in hospital-based study.

The ABO gene locus has been identified to be associated with myocardial infarction in patients with coronary heart disease. The primary focus of this hospital-based study was to explore the relationship of ABO blood groups and ABO genotypes with acute myocardial infarction (AMI) in Karachi, Pakistan. In a comparative cross-sectional study, an equal number of adult AMI patients and healthy controls (n=275 in each group; age range 30-70 years, both males and females) were recruited from the Aga Khan University and NICVD, Karachi, with informed consent. The blood samples were analyzed for ABO blood groups and other biomarkers. PCR followed by RFLP techniques were employed for determining the ABO genotypes. Multinomial regression was used to evaluate the association of genotypes with the risk of AMI. Thirteen different combinations of ABO genotypes were observed while the O2O2 and A2A2 genotypes were not detected. No significant association based on the distribution of blood groups A, B, O and AB among AMI patients and healthy individuals was observed. The odds of AMI were 3.32 times in subjects with BB genotype as compared to subjects with OO genotypes after adjustment of age, gender, body mass index, heart rate, total cholesterol, and waist circumference [AOR (95% CI) =3.32 (1.36-8.08), p-value =0.008]. Our hospital-based study indicates that ABO genotype BB was significantly associated with the risk of AMI. This harmful effect of the BB genotype could have a possible relationship with AMI's development in the Pakistani population.

ABO Incompatibility between the Mother and Fetus Does Not Protect against Anti-Human Platelet Antigen-1a Immunization by Pregnancy.

(1) Background: ABO blood group incompatibility between the mother and fetus protects against anti-D immunization by pregnancy. The possible role of ABO incompatibility in protecting against anti-human platelet antigen-1a immunization is unclear. (2) Methods: This study retrospectively screened 817 families (mother-father-neonate trios) of suspected fetal and neonatal alloimmune thrombocytopenia for inclusion. ABO genotypes were determined in 118 mother-child pairs with confirmed alloimmune thrombocytopenia due to anti-HPA-1a antibodies, and 522 mother-child pairs served as the control group. The expression of blood group antigen A on platelets was determined in 199 consecutive newborns by flow cytometry and compared with adult controls. (3) Results: ABO incompatibility between mother and fetus did not protect against anti-human platelet antigen-1a immunization by pregnancy. ABO blood groups of mothers and/or fetuses were not associated with the severity of fetal and neonatal alloimmune thrombocytopenia. The expression pattern of blood group A antigens on the platelets of newborns mirrored that of adults, albeit on a lower level. Blood group A antigen was detected on a subpopulation of neonatal platelets, and some newborns revealed high platelet expression of A determinants on all platelets (type II high-expressers). (4) Conclusion: The lack of a protective effect of ABO incompatibility between mother and fetus against anti-human platelet antigen-1a immunization by pregnancy may indicate that fetal platelets are not the cellular source by which the mother is immunized.

ODP610 Assessing ABO and Rh Blood Group as a COVID-19 Risk Factor

Abstract Objective Precision medicine harnesses the N-of-1 approach to detect, predict, reverse, and stop progression of disorders of aging through longitudinal observation of biomarkers with respect to genetic makeup. ABO and Rh blood group are two genetic markers that inform risk for dysglycemia, hypercortisolemia, and hypothyroidism, among others. Early in the pandemic, scientists sought to understand whether ABO and Rh blood group was also a risk factor for COVID-19 susceptibility. If proven true, the presence of mutual disease mechanisms between COVID-19 and diseases of the endocrine system may also exist. In the present study, ABO and Rh blood group was examined as a risk factor for COVID-19 susceptibility. Methods Inclusion criteria for this retrospective observational study were an active patient status in December 2019 and a record of ABO and Rh blood group on Quest Laboratory's online portal. ABO and Rh blood groups were compiled and analyzed using chi-square test, odds ratio (OR), and 95% confidence interval (CI) for association to COVID-19 susceptibility. Results 136 adult patients met inclusion criteria for this study, 44 of whom tested positive for COVID-19. The cohort was 30% female, ranging in age from 20-78 years (mean=54 years). In the COVID-19 patients, the respective frequencies of A, B, O, and AB phenotypes were 27.27%, 25. 00%, 38.64%, and 9. 09%. Of these patients, 88.64% were Rh positive. Blood group A (OR = 0.70; CI, 0.32-1.5; p &amp;gt; . 05), group B (OR = 1.58; CI, 0.66-3.78; p &amp;gt; . 05), group O (OR = 0.78; CI, 0.38-1.63, p &amp;gt; . 05), and group AB (OR = 2.97; CI, 0.63-13.9; p &amp;gt; . 05) were not significantly associated with COVID-19 susceptibility. Rh factor was also found to be an insignificant variable (OR = 2. 03; CI, 0.70-5.85; p &amp;gt; . 05). Discussion These findings support the growing body of literature dissociating ABO and Rh blood group from COVID-19 susceptibility. As such, it could be advised that ABO and Rh blood group is not factored into risk stratification for COVID-19 susceptibility in contrast to particular endocrine disorders. A significant limitation of this analysis is that ABO genotypes were unknown. A recent genome-wide association study confirmed a potential involvement of ABO blood group in COVID-19 clinical presentation1. Therefore, deeper analysis may also reveal the mechanistic influence of ABO genotypes on COVID-19 susceptibility, such as the type and quantity of ABO-antibodies in circulation. Further investigation is warranted to determine whether biomarkers known to inform risk of endocrine disorders also influence COVID-19 susceptibility. Understanding what governs this relationship would allow endocrinologists to develop targeted interventions to optimize an individual's health trajectory.

Study on BW.12 Subtype Caused by c.278C>T Mutation in Exon 6 of ABO Gene

To investigate the effect of ABO gene α-1,3-D galactosyl transferase mutation on B antigen expression and its molecular mechanism. The proband and their family members were identified by routine serological methods, and ABO genotyping and sequence analysis were performed by polymerase chain reaction-sequence specificity (PCR-SSP) and direct sequencing of PCR products from exon 1-7 of ABO gene. The 3D structural simulation of mutant proteins was performed by bioinformatics software. The effect of gene mutation on protein structural stability was analyzed. The proband and his family members were subtype B. ABO genotyping indicated that the proband's genotype was Bw12/O. Gene sequencing results confirmed the presence of ABO*BW.12 characteristic variation c.278C>T in the 6th exon of allele B, leading to the replacement of polypeptide chain p.Pro93Leu. The 3D structure simulation analysis of the protein showed that the hydrogen bonds and water molecules connected to the protein changed after amino acid substitution. The family investigation found that the grandfather, father, uncle and brother of the proband all carried the same ABO*BW.12 allele. The mutation of the 6th exon c.278C>T of ABO gene led to the substitution of polypeptide chain amino acids, which affected the stability of α-1,3-D galactosyl transferase protein, resulting in the change of enzyme activity, and the Bw.12 phenotype, which can be stably inherited.

Serological Characteristics and Molecular Biological Mechanism of AEL.02 Subtype

To explore the serological characteristics and molecular biological mechanism of an ael subtype specimen. The ABO blood typing was identified by routine blood group serological and absorption/elution methods; PCR-SBT method for ABO genotyping: 7 exons of ABO gene were amplified by PCR, the amplified products were purified, and then sequencing primers were designed and the amplified products were sequenced directly for analysis; 3D molecular model was constructed and the difference of free energy (ΔΔG) was used to predict the GTA mutant stability. A antigen was not detected on erythrocytes through absorption and elution tests, which was not consistent with the serological characteristics of ael, and the serological typing results were ambiguous. The ABO genotype was ABO*AEL.02/O.01.01, and there were two mutations in exon 7 of the gene, c.467C>T and c.646T>A, which could lead to the replacement of proline with leucine at position 156 (p.Pro156Leu) and phenylalanine with isoleucine at position 216 on the GTA, respectively. The 3D model predicts that the mutations do not introduce new hydrogen bonds to the GTA mutant and do not form a new secondary structure, but can lead to an increase in the ΔΔG value of the GTA mutant, suggesting a decrease in protein stability. The serological characteristics alone is not reliable to determine the ael subype; the ael phenotype may be due to the GTA mutant that reduces enzyme stability.

Genome Reporting for Healthy Populations-Pipeline for Genomic Screening from the GENCOV COVID-19 Study.

Genome sequencing holds the promise for great public health benefits. It is currently being used in the context of rare disease diagnosis and novel gene identification, but also has the potential to identify genetic disease risk factors in healthy individuals. Genome sequencing technologies are currently being used to identify genetic factors that may influence variability in symptom severity and immune response among patients infected by SARS-CoV-2. The GENCOV study aims to look at the relationship between genetic, serological, and biochemical factors and variability of SARS-CoV-2 symptom severity, and to evaluate the utility of returning genome screening results to study participants. Study participants select which results they wish to receive with a decision aid. Medically actionable information for diagnosis, disease risk estimation, disease prevention, and patient management are provided in a comprehensive genome report. Using a combination of bioinformatics software and custom tools, this article describes a pipeline for the analysis and reporting of genetic results to individuals with COVID-19, including HLA genotyping, large-scale continental ancestry estimation, and pharmacogenomic analysis to determine metabolizer status and drug response. In addition, this pipeline includes reporting of medically actionable conditions from comprehensive gene panels for Cardiology, Neurology, Metabolism, Hereditary Cancer, and Hereditary Kidney, and carrier screening for reproductive planning. Incorporated into the genome report are polygenic risk scores for six diseases-coronary artery disease; atrial fibrillation; type-2 diabetes; and breast, prostate, and colon cancer-as well as blood group genotyping analysis for ABO and Rh blood types and genotyping for other antigens of clinical relevance. The genome report summarizes the findings of these analyses in a way that extensively communicates clinically relevant results to patients and their physicians. © 2022 Wiley Periodicals LLC. Basic Protocol 1: HLA genotyping and disease association Basic Protocol 2: Large-scale continental ancestry estimation Basic Protocol 3: Dosage recommendations for pharmacogenomic gene variants associated with drug response Support Protocol: System setup.

Role of the ABO Blood Groups as a Risk Factor for Retinal Vein Occlusion

Introduction: A recent study suggested that non-O blood groups had an increased risk for the presence of retinal vein occlusion (RVO). In this study, we investigated (i) an association between blood group and the presence of RVO and (ii) whether this association correlated to other RVO risk factors. Methods: We included 485 RVO patients and 295 control subjects who were recruited in this case-control study. We determined ABO genotypes rs8176719 as a marker for the O allele and rs8176746 for the B allele by polymerase chain reaction. Results: We did not find an association between ABO blood group and the presence of RVO. In detail, the proportion of ABO blood groups was similar among RVO patients and control subjects (p = 0.527). In a logistic regression, non-O blood group was associated with 1.06-fold higher odds of being a RVO patient (95% CI: 0.78–1.45, p = 0.693), and this lack of association prevailed upon multivariable adjustment for age, gender, history of stroke and venous thromboembolism, and co-medication with lipid-lowering agents. Discussion: Although non-O blood groups are a known risk factor for thrombotic and cardiovascular disease, they do not seem to be a major risk factor for the development of RVO.

The Distribution of ABO blood groups among type 2 Diabetes mellitus patients with or without Chronic Microvascular Complications

The ABO blood group system is highly polymorphic, with more than 20 distinct sub-groups; study findings are usually related to ABO phenotype, but rarely to the ABO genotype and animal models are unsatisfactory because their antigen glycosylation structure is different from humans. Both the ABO and Rh blood group systems have been associated with a number of diseases, but this is more likely related to the presence or absence of these tissue antigens throughout the body and not directly or primarily related to their presence on RBCs. A total of fifty-two 52 patients without complication of DMII, two hundred sixteen 216 patients with complication of DMII and seventy-one 71 person as healthy control were included in the study. The results of the study showed a significant difference in distribution of ABO blood groups between (healthy and DM II subjects) and between (DM II with complication and DM II without complication group), the comparison in the distribution of ABO blood groups among diabetic nephropathy, diabetic retinopathy and diabetic neuropathy groups shows non- significant difference.