Hemoglobin A2 Levels Research Articles

Comparative Efficacy of Low-Carbohydrate and Ketogenic Diets on Diabetic Retinopathy and Oxidative Stress in High-Fat Diet-Induced Diabetic Rats.

This study examined the effect of a low-carbohydrate diet (LCD) and a low-carbohydrate ketogenic diet (LCKD) on diabetic retinopathy in high-fat diet-induced diabetes mellitus in rats and studied the mechanisms of action. Rats were divided into four groups: the Control group, which was fed a normal diet for 16 weeks; the HFD group, which was fed a high-fat diet (HFD) for the first 8 weeks and then switched to a normal diet for 8 weeks; the HFD+LCD group, fed a HFD for 8 weeks followed by an LCD for 8 weeks, and the HFD+LCKD group, which was fed a HFD for 8 weeks followed by an LCKD for 8 more weeks. Both the LCD and the LCKD effectively reduced the final body and total fat weights and decreased fasting serum levels of glucose, insulin, hemoglobin A1 (HbA1C), triglycerides, cholesterol, and LDL-c. They also reduced the levels of malondialdehyde (MDA), tumor necrosis factor-α, vascular endothelial factor, caspapse-3, and bax. In the HFD rats, we found increased serum levels of β-Hydroxybutyrate and upregulated expression of Bcl2, glutathione, superoxide dismutase, and hemeoxygenase-1. Moreover, the LCD and LCKD significantly reduced mRNA levels of Kelch-like ECH-associated protein 1 (Keap1) and enhanced mRNA and nuclear concentrations of nuclear factor erythroid factor 2 (Nrf2). All these effects were associated with improved layers of the retina in the HFD - LCD and HFD + LCKD rats but not in HFD animals. The impact of the LCKD was always more profound on all measured parameters and on improving the structure of the retina compared to the LCD. In conclusion, the LCKD is superior to the LCD in preventing diabetic retinopathy in HFD-fed rats. Mechanistically, our results suggest that the hypoglycemic and hypolipidemic conditions and the Nrf2-dependent antioxidant and anti-inflammatory effects may be involved in the preventative effects of the LCD and LCKD.

Pathology Deterioration in a Pure β-zero Thalassemia Heterozygote After mRNA COVID-19 Vaccination: A Case Report and Literature Review

Background: β-thalassemia heterozygotes produce sensitive levels of fetal hemoglobin and hemoglobin A2 to remain asymptomatic for life compared to β-thalassemia intermedia and β-thalassemia major patients. The asymptomatic β0 thalassemia minor individuals rarely deteriorate to the point of requiring a blood transfusion. Case report: An asymptomatic individual with a pure β0-thalassemia trait, after his first and only Pfizer modified mRNA COVID-19 injection, immediately developed cardiological, neurological, and other clinically important symptoms. The patient’s severe physical impairments resembled a presyncope (about to feint) syndrome. Multiple hematological tests prior to and after the Pfizer injection revealed that the patient sustained a medically important rise in fetal hemoglobin and concurrently a remarkable drop of his hemoglobin A2 levels, compared to prior to mRNA injection. Moreover, the alterations in his life sustaining fetal hemoglobin and hemoglobin A2 levels was accompanied by a clinically significant lowering of blood hemoglobin concentration that required blood transfusion. The patient’s antibody response to the spike protein remains very high (> 10,000 AU/ml) even almost three years after the Pfizer injection. Furthermore, the elevated levels of C-reactive protein — through May 2024 — after the mRNA injection, apart from pointing to multi-organ systemic inflammation, are consistent with his elevated levels of anti-p53 autoantibodies. Conclusions: The simultaneous decrease of patient blood hemoglobin levels was consistent with the hematological readings of mean corpuscular volume, hematocrit, ferritin, folate, and zinc level deteriorations soon after the mRNA injection, which, apart from his double digit rise in C-reactive protein, resemble overall the pathological manifestations of a β-thalassemia worsening condition. By performing an investigative literature review we conclude that an autoimmune hematological disorder contributed to the patient’s severe hematological stress.

HbA2 levels in children with β-thalassemia trait associated with iron deficiency: A perspective for pediatricians.

A critical factor in β-thalassemia trait screening is a hemoglobin A2 (HbA2) level of 3.5% or higher. In children with iron deficiency, HbA2 levels decrease, and diagnosis may be missed. Studies with adult carriers have yielded conflicting results on this issue. The effectiveness of HbA2-based thalassemia screening in carrier children with iron deficiency has not been studied before. In this study, among 213 children with β-thalassemia trait, those with iron deficiency were determined based on ferritin value (<15ng/mL), and their HbA2 levels were examined. We compared HbA2 levels of iron-deficient and iron-sufficient carriers and examined the correlation between low HbA2 levels and ferritin level. Because ferritin is an acute-phase reactant, similar evaluations were made by using transferrin saturation as the criterion for iron deficiency. The median HbA2 value of iron-deficient carrier children was 4.1% and within the diagnostic range (≥3.5%) in the majority of children. Median HbA2 levels in iron-deficient carriers differed from levels in iron-sufficient carriers (4.1% vs 4.9%, P< .007). No correlation was present between low HbA2 levels and ferritin levels (0.226). Furthermore, among children without iron deficiency, there were individuals with low HbA2 levels (26.9%). Similar results were obtained when transferrin saturation was used. Hemoglobin A2 can be used as a screening test in children with β-thalassemia trait, despite accompanying iron deficiency. Low HbA2 levels in these children may be the result of underlying thalassemia mutation, not the result of accompanying iron deficiency. Therefore, in suspected cases of β-thalassemia trait, evaluation should continue, regardless of iron status or treatment.

Post-GWAS Validation of Target Genes Associated with HbF and HbA2 Levels.

Genome-Wide Association Studies (GWASs) have identified a huge number of variants associated with different traits. However, their validation through in vitro and in vivo studies often lags well behind their identification. For variants associated with traits or diseases of biomedical interest, this gap delays the development of possible therapies. This issue also impacts beta-hemoglobinopathies, such as beta-thalassemia and sickle cell disease (SCD). The definitive cures for these diseases are currently bone marrow transplantation and gene therapy. However, limitations regarding their effective use restrict their worldwide application. Great efforts have been made to identify whether modulators of fetal hemoglobin (HbF) and, to a lesser extent, hemoglobin A2 (HbA2) are possible therapeutic targets. Herein, we performed the post-GWAS in vivo validation of two genes, cyclin D3 (CCND3) and nuclear factor I X (NFIX), previously associated with HbF and HbA2 levels. The absence of Ccnd3 expression in vivo significantly increased g (HbF) and d (HbA2) globin gene expression. Our data suggest that CCND3 is a possible therapeutic target in sickle cell disease. We also confirmed the association of Nfix with γ-globin gene expression and present data suggesting a possible role for Nfix in regulating Kruppel-like transcription factor 1 (Klf1), a master regulator of hemoglobin switching. This study contributes to filling the gap between GWAS variant identification and target validation for beta-hemoglobinopathies.

Prevalence of Thalassemia in Nigeria: Pathophysiology and Clinical Manifestations

There is evidence linking genes for thalassaemia, sickle cell diseases, and glucose-6-phosphate dehydrogenase (G6PD) deficiency to a high prevalence of malaria infection. Haemoglobinopathies are hereditary conditions that mostly results in thalassaemia and sickle-cell anaemia. The current global haemoglobin gene carrier population (i.e., healthy individuals who have acquired only one mutant gene from one parent) is between 1 and 5%. Some haemoglobinopathy genes (alpha-thal, beta-thal and HbS) cause alpha-thalassaemia, beta-thalassaemia and sickle-cell anaemia, respectively. Nigerians have a prevalence of 25–30% for sickle cell anaemia (SCA), G6PD, but both alpha thalassaemia and beta thalassaemia are at the lower limit. Thalassaemia and SCA have comparable clinical manifestations. which is quite prevalent in Nigeria? This could lead to underdiagnosis of thalassaemia, which accompany hypochromia and microcytosis, that could be mistaken for iron deficiency anaemia. Depending on the levels of foetal haemoglobin and haemoglobin A2, thalassemia, iron deficiency anaemia, and sickle cell disease continue to be the most common chronic types of anaemia. This review provides details information on the prevalence of thalassaemia in Nigeria and molecular mechanisms in the expression of thalassaemia genes. The authors also suggest various possible way to minimize the occurrences of thalassaemia in Nigeria

A Rare Case of Compound Heterozygous Sickle Cell Beta Thalassaemia with High HbF and Normal HbA2 Levels Detected on HPLC

Compound heterozygous Sickle Haemoglobin (HbS) beta (β) thalassaemia arises from the mutations associated with sickle cell and β thalassaemia and significantly affects populations in low income countries like India. Elevated levels of Haemoglobin A2 (HbA2) represent the primary indicator for identifying carriers of β thalassaemia. However, it’s worth noting that sometimes, High Performance Liquid Chromatography (HPLC) encounters challenges in confirming a final diagnosis when levels of HbA2 and HbS fall outside the diagnostic range. A nine-year-old male and his sister 11-year-old female patient presented with high-grade fever and jaundice since two weeks. Following admission, Complete Blood Count (CBC) and HPLC of both children were done. Hb of male and female child revealed 1.8 g/dL and 1.5 g/dL, respectively. HPLC of male child revealed Haemoglobin F (HbF) 27.4%, HbS 56.3%, HbA2 3.8% and of female child revealed HbF 39.2%, HbS 43.5%, HbA2 3%. HPLC reports of both children were suggestive of differential of compound heterozygous HbS β thalassaemia and HbS homozygous. Later, HPLC of their parents was also done. HPLC of father was suggestive of thalassaemia trait and of mother suggestive of sickle cell trait, following which final diagnosis of both children was given as compound heterozygous HbS β thalassaemia. Diagnosing these compound heterozygous haemoglobinopathies can be challenging. As their is resemblance in clinicopathological features of sickle cell anaemia and β thalassaemia disorders, it is important to carefully differentiate between them although prognosis is better than thalassaemia major or sickle cell anaemia.

Molecular Characterization of Haemoglobin E

Objectives: To detect mutation in cases having haemoglobin A2 level 7percent on high performance liquid chromatography. Method: The cross-sectional, descriptive study was conducted from July 2017 to December 2018 at the Department of Haematology and Human Genetics and Molecular Biology, University of Health Sciences, Lahore, Pakistan, and comprised patients of either gender with haemoglobin A2 7percent. The samples were collected from different cities of Punjab in collaboration with the Punjab Thalassemia Prevention Programme, Lahore. The samples were subjected to complete blood count and high performance liquid chromatography using automated haematology analysers and a beta thalassemia short programme, respectively. To analyse haemoglobin E mutations at the molecular level, polymerase chain reaction-restriction fragment length polymorphism (PCR_RFLP) was performed using a type IIS restriction endonuclease known as Mnl1 (derived from Moraxella nonliquefaciens) to cleave DNA at specific sites and the results were further confirmed on randomly selected samples using Sanger sequencing. Data was analysed using SPSS 25. Results: Of the 39 patients, 15(38.5percent) were males and 24(61.5percent) were females. The overall median age was 14 (23) years. There were 29 (74.4percent) patients a thalassemia family history, and 22(56.4percent) had a positive family history of transfusion related to thalassemia, while no patient had a family history of iron therapy. The media haemoglobin A, haemoglobin A2 and haemoglobin F levels were 72.2 (65.2-79.1) percent, 26.6 (19.1-34.0) percent and 0.9 (-0.8-2.6) percent, respectively. After molecular investigation, HbAE mutation was found in 23(59percent) patients, while wild type HbAA genotype was found in 16(41percent). The heterozygous HbE mutation was present in 23(59percent) patients. Conclusions: Frequently missed/undiagnosed cases of haemoglobin E that co-elute with haemoglobin A2 in the same high performance liquid chromatography window were detected among those with haemoglobin A2 7percent. Key Words: Haemoglobin E, Beta-thalassemia, High performance liquid chromatography, Restriction fragment length polymorphism.

Biallelic hypomorphic variants in CAD cause uridine-responsive macrocytic anaemia with elevated haemoglobin-A2.

Biallelic pathogenic variants in CAD, that encode the multienzymatic protein required for de-novo pyrimidine biosynthesis, cause early infantile epileptic encephalopathy-50. This rare disease, characterized by developmental delay, intractable seizures and anaemia, is amenable to treatment with uridine. We present a patient with macrocytic anaemia, elevated haemoglobin-A2 levels, anisocytosis, poikilocytosis and target cells in the blood smear, and mild developmental delay. A next-generation sequencing panel revealed biallelic variants in CAD. Functional studies did not support complete abrogation of protein function; however, the patient responded to uridine supplement. We conclude that biallelic hypomorphic CAD variants may cause a primarily haematological phenotype.

Molecular characterization of a novel 83.9-kb deletion of the α-globin upstream regulatory elements by long-read sequencing

Inherited deletions of upstream regulatory elements of α-globin genes give rise to α-thalassemia, which is an autosomal recessive monogenic disease. However, conventional thalassemia target diagnosis often fails to identify these rare deletions. Here we reported a family with two previous pregnancies of Hb Bart's hydrops fetalis and was seeking for prenatal diagnosis during the third pregnancy. Both parents had low level of Hemoglobin A2 indicating α-thalassemia. Conventional Gap-PCR and PCR-reverse dot blot showed the father carried –SEA deletion but did not identify any variants in the mother. Multiplex ligation-dependent probe amplification identified a deletion containing two HS-40 probes but could not determine the exact region. Finally, a long-read sequencing (LRS)-based approach directly identified that the exact deletion region was chr16: 48,642-132,584, which was located in the α-globin upstream regulatory elements and named (αα)JM after the Jiangmen city. Gap-PCR and Sanger sequencing confirmed the breakpoint. Both the mother and fetus from the third pregnancy carried heterozygous (αα)JM, and the fetus was normally delivered at gestational age of 39 weeks. This study demonstrated that LRS technology had great advantages over conventional target diagnosis methods for identifying rare thalassemia variants and assisted better carrier screening and prenatal diagnosis of thalassemia.

Prospective screening for δ-hemoglobinopathies associated with decreased hemoglobin A2 levels or hemoglobin A2 variants: A single center experience

Backgroundδ-hemoglobinopathies may lead to misdiagnosis of several thalassemia syndromes especially β-thalassaemia carrier, it is important to evaluate the δ-globin gene defects in areas with high prevalence of globin gene disorders. We describe a prospective screening for δ-hemoglobinopathies in a routine setting in Thailand. MethodsStudy was done on a cohort of 8,471 subjects referred for thalassemia screening, 317 (3.7%) were suspected of having δ-globin gene defects due to reduced hemoglobin (Hb) A2 levels and/or appearance of Hb A2-variants on hemoglobin analysis. Hematologic and DNA analysis by PCR and related assays were carried out. ResultsDNA analysis of δ-globin gene identified seven different δ-globin mutations in 24 of 317 subjects (7.6%). Both known mutations; δ−77(T>C) (n = 3), δ−68(C>T) (n = 1), δ−44(G>A) (n = 8), Hb A2-Melbourne (n = 5), δIVSII−897(A>C) (n = 5), and Hb A2-Troodos (n = 1) and a novel mutation; the Hb A2-Roi-Et (n = 1) were identified. This Hb A2-Roi-Et, results from a double mutations in-cis, δCD82(AAG>AAT) and δCD133(GTG>ATG), was interestingly found in combination with an in trans, 12.6 kb deletional δβ0-thalassemia in an adult Thai woman who had no Hb A2 and elevated Hb F. A multiplex-allele-specific PCR was developed to detect these novel δ-globin gene defects. ConclusionsThe result confirms a diverse heterogeneity of δ-hemoglobinopathies in Thailand which should prove useful in a prevention and control program of thalassemia in the region.

ABNORMAL INTER-ARM SYATOLIC BLOOD PRESSURE DIFFERENCE IN ADULTS WITH CONGENITAL HEART DISEASE

Objective: Many papers have been reported that hypertension and cardiovascular disease are high frequency in adults with congenital heart disease. It is well known that significant inter-arm blood pressure difference can predict cardiovascular risk. We investigate the inter-arm blood pressure difference in adults with congenital heart disease. Design and method: We enrolled 100 consecutive subjects aged 20 years or more, who visited the Department of Adult Congenital Heart Disease, Chiba Cardiovascular Center. The exclusion criteria were history of arrhythmia, which makes accurate pulse wave analysis impossible and history of cardiac operation within 6 months. The patients were classified into 3 groups. The patients in group A had undergone surgery, which sacrifice subclavian arteries (subclavian flap method and original Blalock-Taussig shunt). The patients in group B had undergone surgery to their subclavian arteries, which conserve their subclavian arteries (modified Blalock- Taussig shunt). The patients in group C had not undergone surgery to their subclavian arteries. The bilateral brachial blood pressures were simultaneously measured using form PWV/ABI (Colin, Komaki, Japan). The inter-arm systolic blood pressure difference greater than 10mmHg was defined as significant inter-arm systolic blood pressure difference. Results: Patients’ age was 36.6±14.9 years. Mean difference between bilateral brachial systolic blood pressures was 8.2±13.6 mmHg. Twenty-one patients demonstrated the inter-arm systolic blood pressure difference (29%). Nine patients were classified as group A and all patients in group A demonstrated inter-arm systolic blood pressure difference (29.1±35.6mmHg). Sixteen patients were classified as group B and 9 patients had undergone modified Blalock-Taussig shunt bilaterally. Four patients (44%) in group B demonstrated inter-arm systolic blood pressure difference (bilateral; 3, unilateral: 1). In 75 group C patients, 8 patients (11%) demonstrated inter-arm systolic blood pressure difference. There was no difference between group C patients in with and without the inter-arm systolic blood pressure difference in body mass index, hemoglobin A1 level, lipid profile. Conclusions: The significant inter-arm systolic blood pressure difference in adults with congenital heart disease is not uncommon. The intervention can strongly influence on their inter-arm systolic blood pressure difference.

Identification and Functional Analysis of Known and New Mutations in the Transcription Factor KLF1 Linked with β-Thalassemia-like Phenotypes.

The erythroid transcriptional factor Krüppel-like factor 1 (KLF1) is a master regulator of erythropoiesis. Mutations that cause KLF1 haploinsufficiency have been linked to increased fetal hemoglobin (HbF) and hemoglobin A2 (HbA2) levels with ameliorative effects on the severity of β-thalassemia. With the aim of determining if KLF1 gene variations might play a role in the modulation of β-thalassemia, in this study we screened 17 subjects showing a β-thalassemia-like phenotype with a slight or marked increase in HbA2 and HbF levels. Overall, seven KLF1 gene variants were identified, of which two were novel. Functional studies were performed in K562 cells to clarify the pathogenic significance of these mutations. Our study confirmed the ameliorative effect on the thalassemia phenotype for some of these variants but also raised the notion that certain mutations may have deteriorating effects by increasing KLF1 expression levels or enhancing its transcriptional activity. Our results indicate that functional studies are required to evaluate the possible effects of KLF1 mutations, particularly in the case of the co-existence of two or more mutations that could differently contribute to KLF1 expression or transcriptional activity and consequently to the thalassemia phenotype.

The potential role of vitamin E in patients with glucose-6-phosphate dehydrogenase deficiency: A systematic review and meta-analysis.

As an antioxidant, vitamin E (VitE) may benefit the erythrocytes by protecting glutathione from oxidation by free radicals and peroxide-generating processes. We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement guidelines when reporting this systematic review. We searched 6 electronic databases (PubMed, Scopus, Web of Science, and Cochrane Library) until May 8, 2022. We included all relevant studies. According to the study design, the Cochrane assessment tool (Risk of Bias 2), Risk Of Bias In Non-randomized Studies - of Interventions checklists, and National Institutes of Health tools were used to assess the risk of bias.Continuous data were pooled as a mean difference (MD) with a relative 95% confidence interval. The protocol was registered on PROSPERO (CRD42022333848). Six studies were included in the meta-analysis with a total of 181 patients. Compared with the control group, VitE significantly improved the hemoglobin level for chronic hemolysis (MD = 2.72 g/dL, P < .0001) and for acute hemolysis (MD = 1.18 g/dL, P < .0001). It also decreased the reticulocyte level for chronic hemolysis (MD = -1.39 P < .0001) and for acute hemolysis (MD = -1.42%, P < .0001). For before and after studies, the use of VitE significantly improved the level of packed cell volume (MD = 0.56%, P < .00001), red blood cell half-life (MD = 2.19 days, P < .0001), and decreased the reticulocytes level (MD = -1.41%, P < .00001). Among patients with glucose-6-phosphate dehydrogenase deficiency, VitE might provide benefits such as increasing the hemoglobin, packed cell volume levels, red blood cell half-life, and decreasing the reticulocyte level, so reducing hemolysis. Further high-quality, well-designed randomized controlled trials are recommended.

Molecular genetic characteristics of a family which coinheritance of rare-88 C>G (HBB:c.-138 C>G) β-thalassemia mutation with α-thalassemia and review of the literature

The molecular genetic characteristics of a family with rare -88 C>G (HBB: c.-138 C>G) β-thalassemia gene mutation were studied using cohort study. The cohort study was conducted from June to August 2022 by Prenatal Diagnosis Center of Sanya Women and Children's Hospital Managed by Shanghai Children's Medical Center. The phenotype and genotype were analyzed by hematological cytoanalyzer, automatic electrophoretic analysis system, and next-generation sequencing (NGS). And then, Sanger sequencing was used to verify the rare gene results. The results showed that the proband, her father, her uncle and her younger male cousin had discrete microcytosis (MCV 70.1 fl, 71.9 fl, 73.1 fl and 76.6 fl, respectively) and hypochromia (MCH 21.5 pg,22.0 pg,22.6 pg and 23.5 pg, respectively), elevated hemoglobin A2 level (5.3%, 5.4%, 5.4% and 5.5%, respectively), slightly elevated or normal fetal hemoglobin (Hb F), but no anemia. The proband was identified to have co-inherited ɑ-thalassemia (Hb Westmead gene heterozygous mutation, ɑwsɑ/ɑɑ) and β-thalassemia with a rare -88 C>G (HBB: c.-138 C>G) heterozygous mutation (β-88 C>G/βN). Her mother had the same α-thalassemia as the proband. Her father, her uncle and her younger male cousin had the same rare -88 C>G heterozygous mutations as the proband. While her grandmother and younger brother were not carrier of thalassemia. In conclusion, 4 cases of rare -88 C>G(HBB:c.-138 C>G) heterozygous mutation had been detected in a Chinese family. Carriers of this beta-thalassemia are clinically asymptomatic. This study enriches the knowledge of the thalassemia mutation spectrum in Chinese people and provides valuable information for genetic counseling, prenatal diagnosis, and prevention of thalassemia, providing a scientific basis for improving the quality of birth population and preventing birth defects.

Establishment of haemoglobin A2 reference intervals in Pretoria, South Africa: A retrospective secondary data analysis.

BackgroundHaemoglobinopathies are one of the most common inherited diseases worldwide. Quantification of haemoglobin A2 is necessary for the diagnosis of the beta thalassaemia trait. In this context, it is important to have a reliable reference interval for haemoglobin A2 and a local reference range for South Africa has not been established.ObjectiveThis study aimed to establish reference intervals for haemoglobin A2 using stored patient laboratory data.MethodsThis descriptive study used retrospective data to evaluate haemoglobin A2 levels determined using high-performance liquid chromatography at the National Health Laboratory Service haematology laboratory in Pretoria, South Africa. All tests performed from 01 October 2012 to 31 December 2020 were screened for inclusion; of these, 144 patients’ data met the selection criteria. The reference interval was calculated using descriptive statistics (mean and standard deviation) with a 95% confidence interval.ResultsAnalysed data from enrolled patients showed a normal distribution. The mean age of the patients was 40 years (range: 3–84 years). The reference interval for haemoglobin A2 calculated from this data was 2.3% – 3.6%. The minimum haemoglobin A2 was 2.3% and the maximum was 3.9% with a mean of 2.95% and a standard deviation of 0.357%.ConclusionA normal reference interval has been established for the population served by the laboratory that will assist with accurate diagnosis of the beta thalassaemia trait. This reference interval may also be useful to other laboratories that employ the same technology, especially smaller laboratories where obtaining a sufficiently large number of normal controls may be challenging.

The impact of iron deficiency on the diagnostic level of HbA2 in beta- thalassemia trait from the Sulaimani hemoglobinopathies screening program

Background and objectives: The identification of carriers of beta- thalassemia depends on the detection of a high level of hemoglobin A2. The hemoglobin A2 level is influenced by some elements including iron. The consequence of concomitant iron deficiency on the hemoglobin A2 level is critical in screening laboratories for hemoglobinopathies, particularly in resource-limited ones where molecular identification of hemoglobin A2 levels is unavailable. The aim of this study is to evaluate the consequence of iron deficiency on hemoglobin A2 level to obtain a definite diagnosis of beta- thalassemia trait. Methods: A total of one hundred forty -five subjects were involved, divided into three groups: (50) healthy controls, (50) beta-thalassemia trait, and (45) coincident iron deficiency with beta-thalassemia trait. Full blood count, Iron status including serum iron with total iron-binding capacity, lastly hemoglobin A2 with hemoglobin F estimation were performed for all enrollees. Results: The age range in the beta-thalassemia trait group was 7-40 years, with mean of (26.6± 5.3) years, while the concomitant group has an age range of 15-36 years, with a mean of (24.4 ±5.1) years. Meanwhile the age of control group ranged from 19-36 years with a mean of (24.6 ±3.8) years. The hematological parameters were significantly reduced in beta- thalassemia trait and concomitant iron deficiency in comparison to the controls with no significant difference in hemoglobin A2 between beta thalassemia trait and concomitant iron deficiency (5.1± 0.9) and beta-thalassemia minor (5.2 ± 0.9). Conclusion: No influence of iron deficiency on the identification of beta-thalassemia minor detected in the screened population.

The Clinical Significance of the Spectrum of Interactions of the Rare IVS-II-5 G>C (HBB: c.315+5 G>C) Variation with Other β-Thalassemia Mutations in Southern China.

BackgroundIVS-II-5 G>C (HBB: c.315+5 G>C) is a rare β-thalassemia mutation. However, there is no clear evidence regarding the effect of this defect or co-inheritance of other β-thalassemia mutations on phenotypes.MethodsThe clinical phenotypes associated with compound heterozygosity for the IVS-II-5 G>C mutation and other β-thalassemia mutations, together with the genetic modifiers’ potential effect of the genetic modifiers α-thalassemia, were studied in 13 patients. In addition, analyses of red cell indices, hemoglobin component, iron status, and α-globin genes were carried out in 19 heterozygotes.ResultsNext-generation sequencing of 24 undiagnosed patients with transfusion-dependent thalassemia (TDT) or non-transfusion-dependent thalassemia (NTDT) identified 13 carriers of the IVS-II-5 G>C mutation. There was a wide spectrum of phenotypic severity in compound heterozygotes and 6 (46.2%) of 13 were transfusion dependent. Analysis of 19 heterozygotes indicated that most were hematologically normal without appreciable microcytosis or hypochromia, and approximately half had normal hemoglobin A2 levels at the same time.ConclusionCompound heterozygotes for IVS-II-5 G>C and other severe β-thalassemia mutations are phenotypically severe enough to necessitate appropriate therapy and counselling. Co-inheritance of this nucleotide substitution with other β-thalassemia mutations may account for a considerable portion of the incidence of undiagnosed patients with NTDT and TDT in Guangxi. Therefore, the IVS-II-5 G>C mutation can pose serious difficulties in screening and counselling.

Heterozygosity of the Complex Corfu δ0β+ Thalassemic Allele (HBD Deletion and HBB:c.92+5G>A) Revisited

Simple SummaryThe Corfu δ0β+ thalassemic allele, a unique thalassemic allele combining a deletion of the δ-globin (HBD) and a single nucleotide variant in the β-globin gene (HBB) in cis has, so far, been described only in individuals of Greek origin. The heterozygosity of Corfu δ0β+ is detected in 1–2% of the β-thalassemia carrier population and presents a distinct hematological phenotype of microcytic, hypochromic anemia with normal HbA2 and elevated HbF levels. The study of the Corfu δ0β+ allele is important for genotype resolution, genetic counseling and prenatal/antenatal diagnosis, and the management of patients.The Corfu δ0β+ thalassemic allele is a unique thalassemic allele consisting of the simultaneous presence in cis of a deletion of the δ-globin (Hemoglobin Subunit Delta, HBD) and a single nucleotide variant in the β-globin gene (Hemoglobin Subunit Beta, HBB). The allele has, so far, been described in individuals of Greek origin. The objectives of the study are to ascertain the prevalence of the Corfu δ0β+ allele in comparison to other β-thalassemia variants encountered in Greece using our in-house data repository of 2558 β-thalassemia heterozygotes, and to evaluate the hematological phenotype of Corfu δ0β+ heterozygotes in comparison to heterozygotes with the most common β+- and deletion α0- thalassemia variants in Greece. The results of the study showed a relative incidence of heterozygotes with Corfu δ0β+ at 1.56% of all β-thalassemic alleles, and a distinct hematological phenotype of the heterozygotes characterized by microcytic, hypochromic anemia with normal levels of HbA2 (Hemoglobin A2) and elevated HbF (Hemoglobin F) levels. The application of a specific methodology for the identification of the Corfu δ0β+ allele is important for precise prenatal and antenatal diagnosis programs in Greece.

Problem of borderline hemoglobin A2 levels in an Iranian population with a high prevalence of \u03b1- and \u03b2-thalassemia carriers

BackgroundIt is difficult to classify a small fraction of α- and β-thalassemia (α- and β-thal) carriers based on their Hb A2 levels. Here, we report the results of a molecular investigation in a cohort of thalassemia carriers with borderline Hb A2 levels originated from western Iran.ResultsThe documents of 5956 α- or β-thal carriers were reviewed. The frequency of individuals with borderline Hb A2 levels in this cohort was 436 (7.32%). A total of 12 different α-thal and 27 different β-thal variants were identified in this study.ConclusionsOur data showed that individuals with borderline Hb A2 are not uncommon in our population. Moreover, preselection of α- and β-thal carriers with borderline Hb A2 levels based on Hb A2, mean corpuscular volume (MCV), and mean cell hemoglobin (MCH) is not advisable in our population. Therefore, it is necessary to investigate both α- and β-globin genes in cases with borderline Hb A2 levels, especially if the partner is a carrier of β-thal or α0-thal.

Clinical and Hematological Profile of β-Thalassemia Minor

Background: β-thalassemia minor is the most common inherited hemoglobinopathy worldwide. The defect lies in the beta globin chain synthesis as a result of mutations in beta globin chain genes. Clinical presentation is variable, ranging from normal hemoglobin to severe anemia. Haematologically, classically, there is microcytosis, hypochromia, raised red blood cell count, and elevated HbA2 on hemoglobin studies. But these findings considerably overlap with some added factor, such as, isolated or combine nutritional deficiencies. Aims: To evaluate the clinical and hematological profile of β-thalassemia minor cases, and, to make a protocol to investigate the patients having microcytic hypochromic anemia for carrier state of hemoglobinopathies especially thalassemia. Study Design: Descriptive study. Place and duration of study: Hematology OPD, Faisalabad Institute of Cardiology, Faisalabad from 1st January 2018 to 31st December 2020. Methodology: 3520 patients were referred to our clinic for workup of microcytic hypochromic anemia. CBC and HbA2 testing was done on all cases. Out of those, 111 fell into our criteria of the diagnosis of β-thalassemia minor. Results: Ninety one (81.9%) of the patients presented with pallor. Tachycardia and shortness of breath was a complaint in 46 (41.4%) and 30 (27%) respectively. The hemoglobin mean of 9.1 (range 2.7-14.5 g/dL). Red cell distribution width RDW-CV of RBCs was ≤18% in 48.6% of the patients. Mean MCV was 73.3fL (range 54-156), mean RBCs count was 4.75 (range 0.8-7.6). Hemoglobin on HPLC of Biorad Variant II Beta Thalassemia Short Program revealed a raised HbA2 in 100% of the patients of β-thalassemia minor. Iron deficiency was found to be in 35% of the total diagnosed β-thalassemia minor patients with mean concentration of Ferritin 13.3 ng/mL (range 0.8-80). Conclusions: All patients with microcytic, hypochromic anemia and raised RBC count should be screened on HPLC for demonstration of HbA2 to exclude β-thalassemia minor. Microcytosis (MCV &lt;76fL), Borderline raised RBC count (RBCs &gt;5x1012/L), Borderline high or low RDW (&lt;18), and a raised HbA2 level are highly consistent with the diagnosis of β-thalassemia minor. Keywords: β-thalassemia minor, Hemoglobin A2 (HbA2), Microcytic hypochromic Anemia, HPLC, Thalassemia minor