Analysis of the Origin of Emiratis as Inferred from a Family Study Based on HLA-A, -C, -B, -DRB1, and -DQB1 Genes.

In this study, we investigated HLA class I and class II allele and haplotype frequencies in Emiratis and compared them to those of Asian, Mediterranean, and Sub-Saharan African populations. METHODS: Two-hundred unrelated Emirati parents of patients selected for bone marrow transplantation were genotyped for HLA class I (A, B, C) and class II (DRB1, DQB1) genes using reverse sequence specific oligonucleotide bead-based multiplexing. HLA haplotypes were assigned with certainty by segregation (pedigree) analysis, and haplotype frequencies were obtained by direct counting. HLA class I and class II frequencies in Emiratis were compared to data from other populations using standard genetic distances (SGD), Neighbor-Joining (NJ) phylogenetic dendrograms, and correspondence analysis. RESULTS: The studied HLA loci were in Hardy-Weinberg Equilibrium. We identified 17 HLA-A, 28 HLA-B, 14 HLA-C, 13 HLA-DRB1, and 5 HLA-DQB1 alleles, of which HLA-A*02 (22.2%), -B*51 (19.5%), -C*07 (20.0%), -DRB1*03 (22.2%), and -DQB1*02 (32.8%) were the most frequent allele lineages. DRB1*03~DQB1*02 (21.2%), DRB1*16~DQB1*05 (17.3%), B*35~C*04 (11.7%), B*08~DRB1*03 (9.7%), A*02~B*51 (7.5%), and A*26~C*07~B*08~DRB1*03~DQB1*02 (4.2%) were the most frequent two- and five-locus HLA haplotypes. Correspondence analysis and dendrograms showed that Emiratis were clustered with the Arabian Peninsula populations (Saudis, Omanis and Kuwaitis), West Mediterranean populations (North Africans, Iberians) and Pakistanis, but were distant from East Mediterranean (Turks, Albanians, Greek), Levantine (Syrians, Palestinians, Lebanese), Iranian, Iraqi Kurdish, and Sub-Saharan populations. CONCLUSIONS: Emiratis were closely related to Arabian Peninsula populations, West Mediterranean populations and Pakistanis. However, the contribution of East Mediterranean, Levantine Arab, Iranian, and Sub-Saharan populations to the Emiratis' gene pool appears to be minor.

Development of a calculated panel reactive antibody calculator for the United Arab Emirates: a proof of concept study.

Calculated panel reactive antibody (CPRA) is used to help increase sensitized patient's access to transplantation. United Arab Emirates (UAE) has a diverse resident population hence we developed a UAE-CPRA calculator based on HLA antigen frequencies of the different ethnic groups that represent the UAE population. HLA antigen frequencies at serological split antigen level for HLA-A, -B, -C, -DRB1 and -DQB1 of 1002 healthy unrelated donors were performed. We subsequently compared the performance of the UAE CPRA calculator with the Organ Procurement and Transplantation Network (OPTN) and the Canadian CPRA calculators in 110 Kidney Transplant waitlist patients from January 2016 to December 2018. Lin's concordance correlation coefficient showed a moderate agreement between the UAE and OPTN calculator (Rc = 0.949, 95% CI 0.929-0.963) and the UAE and Canadian calculators (Rc = 0.952, 95% CI 0.932-0.965). While there continued to be a moderate agreement (Rc = 0.937, UAE versus OPTN calculator) in the lower sensitized group, a poor agreement (Rc = 0.555, UAE versus OPTN calculator) was observed in the higher sensitized group. In this study, we provide a template for countries to develop their own population-specific CPRA calculator. Implementation of the CPRA algorithm based on HLA frequencies of the multi-ethnic UAE population will be more fitting to increase access to transplantation and improve transplant outcomes. Our study demonstrates that the CPRA calculators developed using the data from the western population had poor correlation in our higher sensitized patients disadvantaging them in potential organ allocations systems. We plan to further refine this calculator by using high resolution HLA typing to address the problem of a genetically diverse population.

Continuous subcutaneous insulin infusion is associated with a better glycemic control than multiple daily insulin injections without difference in diabetic ketoacidosis and hypoglycemia admissions among Emiratis with Type 1 diabetes.

AIMS: To characterizes Emiratis patients with Type 1 diabetes (T1D) and compares outcomes between continuous subcutaneous insulin infusion (CSII) versus multiple daily insulin injections (MDI) users. The WHO-Five Well-Being Index (WHO-5) score was used to screen for depression. METHODS: In this cross-sectional study; sociodemographic, clinical characteristics and insulin replacement regimens were collected on patients with T1D between 2015-2018. RESULTS: 134 patients with mean age of 20.9±7.5 years were included. Females constitute 56.7% and 50.7% had diabetes duration of >10 years. Diabetic ketoacidosis (DKA) at presentation was reported in 46.3%. Average glycemic control over preceding 12months was satisfactory (less than 7.5%), suboptimal (7.5-9%), and poor (more than 9%) in 26.6%, 42.7% & 30.6% of the patients, respectively. Higher proportion of patients using CSII achieved satisfactory or suboptimal glycemic control compared to patients with MDI (P = 0.003). The latest median /IQR HbA1c was significantly lower (P = 0.041) in patients using CSII (8.2 /1.93%) compared to MDI (8.5/2.45%). There was no significant difference between two groups in DKA, severe hypoglycemia or total WHO-5 score. CONCLUSIONS: CSII usage was associated with better glycemic control than MDI, although no difference in DKA and severe hypoglycemia. The overall glycemic control among Emiratis subjects with T1D is unsatisfactory and needs more rigorous patient counseling and education.

HLA-DRB1 and -DQB1 Alleles, Haplotypes and Genotypes in Emirati Patients with Type 1 Diabetes Underscores the Benefits of Evaluating Understudied Populations.

Background: HLA class II (DR and DQ) alleles and antigens have historically shown strong genetic predisposition to type 1 diabetes (T1D). This study evaluated the association of DRB1 and DQB1 alleles, genotypes, and haplotypes with T1D in United Arab Emirates. Materials and Methods: Study subjects comprised 149 patients with T1D, and 147 normoglycemic control subjects. Cases and controls were Emiratis and were HLA-DRB1 and -DQB1 genotyped using sequence-based typing. Statistical analysis was performed using Bridging Immunogenomic Data-Analysis Workflow Gaps R package. Results: In total, 15 DRB1 and 9 DQB1 alleles were identified in the study subjects, of which the association of DRB1*03:01, DRB1*04:02, DRB1*11:01, DRB1*16:02, and DQB1*02:01, DQB1*03:02, DQB1*03:01, and DQB1*06:01 with altered risk of T1D persisted after correcting for multiple comparisons. Two-locus haplotype analysis identified DRB1*03:01∼DQB1*02:01 [0.44 vs. 0.18, OR (95% CI) = 3.44 (2.33-5.1), Pc = 3.48 × 10-10]; DRB1*04:02∼DQB1*03:02 [0.077 vs. 0.014, OR = 6.06 (2.03-24.37), Pc = 2.3 × 10-3] and DRB1*04:05∼DQB1*03:02 [0.060 vs. 0.010, OR = 6.24 (1.79-33.34), Pc = 0.011] as positively associated, and DRB1*16:02∼DQB1*05:02 [0.024 vs. 0.075, OR = 0.3 (0.11-0.74), Pc = 0.041] as negatively associated with T1D, after applying Bonferroni correction. Furthermore, the highest T1D risk was observed for DR3/DR4 [0.104 vs. 0.006, OR = 25.03 (8.23-97.2), Pc = 2.6 × 10-10], followed by DR3/DR3 [0.094 vs. 0.010, OR = 8.72 (3.17-25.32), Pc = 3.18 × 10-8] diplotypes. Conclusion: While DRB1 and DQB1 alleles and haplotypes associated with T1D in Emiratis showed similarities to Caucasian and non-Caucasian populations, several alleles and haplotypes associated with T1D in European, African, and Asian populations, were not observed. This underscores the contribution of ethnic diversity and possible diverse associations between DRB1 and DQB1 and T1D across different populations.

Detection of the novel allele, A*01:380:01:02, in a Bahraini individual by next generation sequencing.

HLA-A*01:380:01:02 is a variant of A*01:01:01:01, differing by five nucleotide substitutions.

A Review of COVID-19 Mass Testing in the United Arab Emirates.

Appropriate diagnostic testing to identify persons infected with SARS-COV-2 is a vital part of a health system's ability to control the global pandemic of COVID-19 disease. The primary purpose of this review is to provide an overview of the mass testing strategy implemented throughout the UAE and the overall impact it has made on containing and controlling the spread of the disease. This study describes the mass testing strategy and capacity of the UAE during the pandemic of the new coronavirus SARS-COV-2. The UAE has conducted 15 million polymerase chain reaction (PCR) tests to SARS-COV-2, as of 15 November 2020. The number of tests per day varied from 10,000 by the end of March to 120,000 tests per day in November 2020. The mass testing initiative across the entire UAE forms an integral part of a bigger strategy focusing on testing, tracing contacts and isolating positive cases.

High-resolution HLA allele and haplotype frequencies in several unrelated populations determined by next generation sequencing: 17th International HLA and Immunogenetics Workshop joint report.

The primary goal of the unrelated population HLA diversity (UPHD) component of the 17th International HLA and Immunogenetics Workshop was to characterize HLA alleles at maximum allelic-resolution in worldwide populations and re-evaluate patterns of HLA diversity across populations. The UPHD project included HLA genotype and sequence data, generated by various next-generation sequencing methods, from 4,240 individuals collated from 12 different countries. Population data included well-defined large datasets from the USA and smaller samples from Europe, Australia, and Western Asia. Allele and haplotype frequencies varied across populations from distant geographical regions. HLA genetic diversity estimated at 2- and 4-field allelic resolution revealed that diversity at the majority of loci, particularly for European-descent populations, was lower at the 2-field resolution. Several common alleles with identical protein sequences differing only by intronic substitutions were found in distinct haplotypes, revealing a more detailed characterization of linkage between variants within the HLA region. The examination of coding and non-coding nucleotide variation revealed many examples in which almost complete biunivocal relations between common alleles at different loci were observed resulting in higher linkage disequilibrium. Our reference data of HLA profiles characterized at maximum resolution from many populations is useful for anthropological studies, unrelated donor searches, transplantation, and disease association studies.

Characterization of the novel allele HLA-DRB1*01:01:36 in an Emirati donor.

HLA-DRB1*01:01:36 is a variant of DRB1*01:01:01, differing by three single nucleotide substitutions.

Association of variants in PTPN22, CTLA-4, IL2-RA, and INS genes with type 1 diabetes in Emiratis.

Type 1 diabetes (T1D) is a chronic autoimmune disease with a complex interrelation of genetic and environmental factors. Genetic studies have reported HLA and non-HLA loci as significant contributors to T1D. However, the genetic basis of T1D among Emiratis is unexplored. This study aims to determine the contribution of four genes PTPN22, CTLA-4, IL2-RA, and INS to T1D risk among Emiratis. The association between variants in PTPN22 (rs2476601, rs1310182), CTLA-4 (rs11571316, rs231775, rs3087243, rs1427676, and rs231727), IL2-RA (rs7090530), and INS (rs7111341) with T1D was tested in 310 Emiratis (139 T1D patients and 171 controls). A significant association was found at rs1310182, and rs2476601 both in PTPN22, rs3087243, and rs231775 both in CTLA-4, and rs12251307 in IL2-RA. Moreover, a haplotype constituted from GG and AG genotypes at rs231727 and rs231775, respectively, in CTLA-4 was significantly associated with an increased T1D risk. The cumulative effects of risk alleles for all significantly associated SNPs showed 11.8 higher relative risk for T1D for those who carry 5-6 compared to 0-1 risk alleles. This study illustrated that PTPN22, CTLA-4, and IL2-RA gene variants could confer risk alleles for T1D among the Emirati population.

Identification of the novel HLA-A*26:206N allele by next generation sequencing in an Emirati bone marrow donor.

Nucleotide sequence of HLA-A*26:206N differs from HLA-A*26:01:01 at genomic position g.1183 G>A.

Measures of gluten-related reactivity in children with autism spectrum disorders in the absence of overt gastrointestinal symptoms: a pilot study from the United Arab Emirates.

OBJECTIVES: The aetiology of autism spectrum disorder (ASD) is multifactorial, sometimes genetic, and may be associated with abnormal immunological responses to peptides from proteins such as gluten. These peptides may cross the blood-brain barrier and affect neurotransmission, resulting in behavioural symptoms consistent with ASD. The aim of this study was to screen for markers of gluten-related immune reactivity in the absence of overt gastrointestinal symptoms in patients with ASD in the United Arab Emirates, a country associated with a high prevalence of ASD but lacking this type of research. METHODS: Patients diagnosed with ASD (using Diagnostic and Statistical Manual of Mental Disorders-IV-based criteria and Autism Diagnostic Observational Schedules) were compared with controls, regarding anti-tissue transglutaminase (tTG) immunoglobulin (Ig) A and anti-deamidated gliadin peptide (DGP) IgA levels. RESULTS: Sixty-six patients with ASD and 101 controls were included. Patients with ASD showed statistically significant lower anti-DGP IgA levels, but no significant difference in anti-tTG IgA levels, versus healthy controls. Correlations between immunological data and clinical symptoms were synergistic, but not statistically significant. CONCLUSION: ASD may be associated with reduced levels of anti-DGP IgA.

HEM1 deficiency disrupts mTORC2 and F-actin control in inherited immunodysregulatory disease.

Immunodeficiency often coincides with hyperactive immune disorders such as autoimmunity, lymphoproliferation, or atopy, but this coincidence is rarely understood on a molecular level. We describe five patients from four families with immunodeficiency coupled with atopy, lymphoproliferation, and cytokine overproduction harboring mutations in NCKAP1L, which encodes the hematopoietic-specific HEM1 protein. These mutations cause the loss of the HEM1 protein and the WAVE regulatory complex (WRC) or disrupt binding to the WRC regulator, Arf1, thereby impairing actin polymerization, synapse formation, and immune cell migration. Diminished cortical actin networks caused by WRC loss led to uncontrolled cytokine release and immune hyperresponsiveness. HEM1 loss also blocked mechanistic target of rapamycin complex 2 (mTORC2)-dependent AKT phosphorylation, T cell proliferation, and selected effector functions, leading to immunodeficiency. Thus, the evolutionarily conserved HEM1 protein simultaneously regulates filamentous actin (F-actin) and mTORC2 signaling to achieve equipoise in immune responses.

Good outcome of the single-center pediatric kidney transplant program in Abu Dhabi.

Renal transplantation is the treatment of choice for ESRD in children. It is associated with better quality of life, growth of children, and improved long-term survival. The aim of the study was to evaluate the outcomes of pediatric renal transplantation at a tertiary care center in UAE. A retrospective chart review was undertaken for all the pediatric renal transplants performed at Sheikh Khalifa Medical City, Abu Dhabi, UAE, over the past 9 years. The study evaluated the demographic data, outcomes, and complications of pediatric renal transplantation. The post-transplantation outcomes including surgical complications, documented infections, graft rejection, graft and patient survival, effect on growth, and eGFR were reviewed. Between 2010 and 2018, 30 pediatric patients underwent renal transplantation. The follow-up period ranged from 1 to 9 years with a mean of 3.3 years. The mean age of the patients at the time of transplant was 9.8 years, and 56.7% were males. Prior to the transplantation, the majority of the recipients were on peritoneal dialysis (70.0%). Main source of renal donation at our center was from LRD, chiefly from parents. Patient survival at 1 and 5 years was 100% and 96.7%, respectively. Graft survival at 1 and 5 years was 96.7% and 83.3%, respectively. During the 9-year follow-up period, 5 (16.7%) recipients experienced rejection episode. This study demonstrates that during 5-year period, pediatric kidney transplantation program has achieved optimal patient (96.7%) and graft (83.3%) survival rates and is comparable to well-established centers.

Identification of a novel HLA-C allele, HLA-C*16:123N, in an Emirati blood donor.

The novel allele HLA-C*16:123N has a single nucleotide difference with HLA-C*01:02:01:01 in exon 2.