Comparison of the characteristics of two hemoglobin variants, Hb D-Iran and Hb E, eluting in the Hb A2 window

BACKGROUND: Cation exchange-high performance liquid chromatography (CE-HPLC) is most commonly used to evaluate hemoglobin (Hb) variants, which elute in the Hb A2 window. This study aimed to assess prevalence of an uncommon Hb variant, Hb D-Iran, and compare its red cell parameters and peak characteristics with those of Hb E that commonly elutes in the Hb A2 window. METHODS: Generally, we assess abnormal Hb using CE-HPLC as the primary technique along with alkaline and acid electrophoresis. All cases with Hb A2 window >9%, as assessed by CE-HPLCs during 2009–2013, were selected. RESULTS: Twenty-nine cases with Hb D-Iran variant were identified—25 heterozygous, 2 homozygous, 1 compound heterozygous Hb D-Iran/β-thalassemia, and 1 Hb D-Iran/Hb D-Punjab. Overall prevalence of Hb D-Iran was 0.23%. Compared to patients with Hb E, those with Hb D-Iran had significantly higher Hb (12.1 vs. 11.3 g/dL, P=0.03), MCV (82.4 vs. 76.4 fL, P=0.0044), MCH (27.9 vs. 25.45 pg, P =0.0006), and MCHC (33.9 vs. 33.3 g/dL, P=0.0005). Amount of abnormal Hb (40.7 vs. 26.4%, P=0.0001) was significantly higher while retention time (3.56 vs. 3.70 min, P=0.0001) was significantly lower in Hb D-Iran than in Hb E. CONCLUSION: Hb D-Iran peak can be easily missed if area and retention time of the Hb A2 window are not carefully analyzed. To distinguish between variants, careful analysis of peak area and retention time is sufficient in most cases and may be further confirmed by the second technique—alkaline electrophoresis.

Hemoglobin E genotypes and fertility: a study among the Ahom of Upper Assam, India.

Background: Differential fertility is reported in areas where prevalence of hemoglobin E (Hb E) is high. At this backdrop a representative Ahom sample from Upper Assam is studied to examine if differential fertility exist between Hb E and normal Hb A mothers and whether there is significant difference between them with regard to the hemoglobin (Hb) concentration. Methods: Detailed reproductive histories are collected from 119 Ahom couples followed by Hb typing by ‘Cellulose Acetate Gel’ electrophoresis (pH 8.9) and fetal hemoglobin (Hb F) determined by Acid Elution technique. Hb concentration (in g/dl) is measured by Sahley’s method. Results: The calculated Hb E allele frequencies for the Ahom male and the female subjects are 0.424 and 0.403 respectively. β-carrier frequency in the total sample is found to be 0.42%. There is no differential fertility observed between Hb A/Hb A (AA), Hb A/Hb E (AE) and Hb E/Hb E (EE) mothers. Reproductive performance of the couples revealed that the mothers with an Hb E complement either heterozygous or homozygous are more likely to have a spontaneous abortion or an infant mortality. Conclusions: It may be concluded that Hb E induced anemia may increase spontaneous abortion and infant mortality in AE and EE mothers.

Hemoglobinopathies in South Gujarat population and incidence of anemia in them.

Objective: To Screen of South Gujarat population for determination of prevalence of different hemoglobinopathies particularly beta thalassemia trait (BTT) and sickle cell trait (SCT) and find out the incidence of anemia in them. Material and Methods: The present study screened 32,857 samples of students from different school and colleges in South Gujarat. Blood samples were initially tested for solubility test and complete hemogram on hematology analyzer. Samples having MCV (≤78), MCH (≤28) and/or positive solubility test were investigated for Hb electrophoresis on cellulose acetate membrane (pH 8.6). Hb A 2 level ≥3.5% was considered as diagnostic for BTT. High performance liquid chromatography on Biorad Hb variant system was done on samples having doubtful results. Result: Overall prevalence of BTT and SCT in South Gujarat was 4.4% and 1.3% respectively. Gamit, Vasava, Chaudhary, and Mahyavanshi castes had high prevalence of BTT (15.9%, 13.6%, 12.6%, and 6.9%) as well as SCT (22.2%, 15.2, 22.3, and 4.2%) respectively. Other communities like Lohana (10.8%), Sindhi (10.2%), Prajapati (6.3%), and Ghanchi (6.2%) also showed higher prevalence of BTT. Incidence of mild to moderate anemia was higher in BTT and SCT compared to non-BTT or non-SCT subjects. Conclusion : Study suggests that BTT is the most prevalent hemoglobinopathy in South Gujarat. β-thalassemia and Sickle cell anemia are highly prevalent in Mahyavanshi, Chaudhary, Gamit, Vasava and Rohit. Prajapati, Lohana, Leva Patel, and Ghanchi have β- thalassemia risk. SCT is more frequently detected in Dhodia Patel and Kukanas.

Haemoglobinopathies in Southeast Asia.

In Southeast Asia α-thalassaemia, β-thalassaemia, haemoglobin (Hb) E and Hb Constant Spring (CS) are prevalent. The abnormal genes in different combinations lead to over 60 different thalassaemia syndromes, making Southeast Asia the locality with the most complex thalassaemia genotypes. The four major thalassaemic diseases are Hb Bart's hydrops fetalis (homozygous α-thalassaemia 1), homozygous β-thalassaemia, β-thalassaemia/Hb E and Hb H diseases. α-Thalassaemia, most often, occurs from gene deletions whereas point mutations and small deletions or insertions in the β-globin gene sequence are the major molecular defects responsible for most β-thalassaemias. Clinical manifestations of α-thalassaemia range from asymptomatic cases with normal findings to the totally lethal Hb Bart's hydrops fetalis syndrome. Homozygosity of β-thalassaemia results in a severe thalassaemic disease while the patients with compound heterozygosity, β-thalassaemia/Hb E, present variable severity of anaemia, and some can be as severe as homozygous β-thalassaemia. Concomitant inheritance of α-thalassaemia and increased production of Hb F are responsible for mild clinical phenotypes in some patients. However, there are still some unknown factors that can modulate disease severity in both α- and β-thalassaemias. Therefore, it is possible to set a strategy for prevention and control of thalassaemia, which includes population screening for heterozygotes, genetic counselling and foetal diagnosis with selective abortion of affected pregnancies.

Serum Hepatitis B Virus (HBV)DNA Levels at Different Stages of Clinical Course in Patients with Chronic HBV Infection in an Endemic Area

The aims of this study were to investigate serum hepatitis B virus (HBV) DNA levels at different clinical stages in patients with chronic HBV infection, and to determine the serum HBV DNA level that discriminated HBeAg-negative chronic hepatitis B(CHB) cases from inactive HBsAg carriers. In all, 222 patients, encompassing 68 HBeAg-positive CHB patients (HBeAg-positive, ALT-elevation), 89 HBeAg-negative CHB patients (HBeAg-negative, ALT-elevation), and 65 inactive HBsAg carriers (HBeAg-negative, ALT-normal), were tested. The ALT levels had been tested more than twice during the previous six months, and the serum HBV DNA levels were quantified by a polymerase chain reaction-based assay. The serum HBV DNA levels of the HBeAg-negative patients were significantly lower than those of the HBeAg-positive patients (median 2.7 x 10(4) vs. 1.6 x 10(8) copies/mL; p=0.000). In addition, the HBV DNA levels of the HBeAg-negative CHB patients were significantly higher than those of the inactive HBsAg carriers (median 2.2 x 10(5) vs. 3.2 x 10(3) copies/ mL; p=0.000). The optimal HBV DNA level for discriminating HBeAg-negative CHB cases from inactive HBsAg carriers was 2.0 x 10(4) copies/mL. The serum HBV DNA levels were lower than the cutoff value in 72.3% (47/65) of the inactive HBsAg carriers, and in 31.5% (28/89) of the HBeAg-negative CHB patients. The serum HBV DNA levels differed significantly between these two groups. However, the levels in the two groups overlapped extensively, preventing the definition of a differentiation cut-off value.