Hb Q-India Research Articles

Prevalence and spectrum of haemoglobinopathies in females of reproductive age group- A first tertiary care center experience in Punjab, North India.

Thalassemia and hemoglobinopathies are a group of inherited conditions characterized by abnormalities in the synthesis or structure of hemoglobin (Hb). According to estimates, approximately 7% of the world population is a carrier of Hb disorders, leading to high morbidity and mortality. To reduce the burden of these highly prevalent monogenic disorders, detecting them in the carrier stage is crucial to prevent disease progression. We aimed to estimate the prevalence and spectrum of hemoglobinopathies in females in the reproductive (20-40 years) age group. It was a retrospective observational study carried out for 2.5 years (from January 2018 till June 2020). All the females in the age group of 20-40 years age whose blood samples were received in the department for High-Performance Liquid Chromatography (HPLC) were included. The cases with abnormal HPLC findings were analyzed for hematological parameters including hemoglobin, RBC count, and RBC indices [mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), mean corpuscular hemoglobin concentration (MCHC), & red cell distribution width - coefficient of variation (RDW-CV)]. Statistical package for social science (SPSS) statistics 21 version for Microsoft Windows (Chicago, USA) was used for statistical analysis of data. The data were described in terms of range, mean ± standard deviation (SD), frequencies (number of cases), and relative frequencies (percentage) as appropriate. During the study period, 72.2% of the females were affected with β-thalassemia trait, followed by HbD Punjab trait (17.8%), HbQ India trait (2.9%), β-thalassemia major (1.8%), and two cases (1.2%) each of HbS trait, HbD Iran trait, and compound heterozygous of HbD Punjab and β-thalassaemia, whereas HbE trait, compound heterozygous of HbQ and β-thalassemia, compound heterozygous of HbJ-variant and β-thalassemia had one case each (0.6%). Preventive strategies are cost-effective and include population screening, premarital screening, screening of spouses, genetic counseling, and prenatal diagnosis. Educating the carrier females about the potential risk and various screening methods may help in controlling the disease.

Screening of Dry Blood Spots from Newborns by Two High Performance Liquid Chromatography (HPLC) Systems: A Comparison of Their Ability to Diagnose Both Sickle and Non-sickle Hemoglobinopathies.

Screening of newborns for the presence of sickle hemoglobin (HbS) is aimed at reducing the morbidity and mortality associated with sickle cell disease in early childhood. The high cost and limited availability of dedicated high performance liquid chromatography (HPLC) systems specially designed for screening of dry blood spots (DBS), however, restrict a wider application of this preventive approach. Therefore, we examined the ability of a commonly used HPLC system for detection of hemoglobinopathies in DBS samples in order to find an alternative for the dedicated newborn screening (NBS) HPLC system. DBS samples from 7522 newborns were first examined by Variant NBS HPLC system (Bio Rad, USA) for the presence of hemoglobinopathies. Positive samples were then analysed by Variant II system (Bio Rad, USA), another platform commonly used for hemoglobinopathy screening of anticoagulated blood samples. Eighty six newborns (1.1%) showed the presence of hemoglobinopathies (HbS 28, HbE 21, HbD 27, HbQ India 9 and Hb Barts 1) by Variant NBS system-all in heterozygous state. There was 100% correlation between the two sets of results obtained by the two HPLC systems. Newborns with HbQ India showed an additional Hb peak in HPLC resulting from combination of the abnormal alpha globin chain of HbQ India with the normal gamma chain of HbF-'HbF Q India'. Variant II HPLC system, used for routine hemoglobinopathy screening in anticoagulated blood, can also be used for screening DBS samples. This obviates the need for a dedicated NBS system for hemoglobinopathy screening in newborns. We also demonstrated that both the systems are equally competent in detecting non-sickle Hb variants in DBS samples.

Study of prevalence of haemoglobin disorders in sindhi community with reference to HPLC

Introduction: Inherited haemoglobin disorders are major health problems in certain communities in different geographical areas in India. These disorders pose a huge burden on affected families physically, financially & psychologically. This study is carried out to find the Prevalence of these disorders in Sindhi community in Aurangabad city in state of Maharashtra, India. Materials and Methods: The present cross-sectional study was undertaken among 338, apparently healthy Sindhi individuals from community in Aurangabad, Maharashtra from July 2014 to March 2017. All the samples were tested in automated hematology cell counter and then for HPLC on Bio-Rad variant classic. Various CBC parameters and Hemoglobin patterns were derived on all samples. Result: The overall prevalence of Hemoglobinopathy was 60/338 (17.75%), comprised of 42 (12.42%) cases of BTT, 3 (0.88%) cases of BTM, 3 (0.88%) cases of SCT, 11 (3.25%) cases of Hb Q-India & One (0.29%) case of Hb Q-India+BTT. Conclusion: Out of 338 samples, BTT and Hb Q-India were found to be more common Hb disorders in Sindhi community. Screening of community and counselling regarding the nature of these disorders are very important measures to reduce the burden of disease. Keywords: Hemoglobin disorders, Prevalence, HPLC, β-thalassemia trait, Hb Q-India, Maharashtra, India.

A Wide Spectrum Study of α-Globin Chain Variants: Cases from the UK

Over many years, cases of suspected α-globin chain variants were collected from different parts of the UK. The suspicion was based on the clinical picture, high performance liquid chromatography (HPLC) variant percentage, retention time (RT) and isoelectric focusing (IEF). DNA sequencing and the restriction enzyme EaeI were used for definitive diagnosis. One hundred and forty-eight variants were confirmed on one or both of the two α-globin genes (HBA2, HBA1). These cases were identified as 46 different α-globin chain variants. The most common variants were Hb J-Meerut [HBA2: c.362C>A (or HBA1)] (10.1%) and Hb Q-India (HBA1: c.193G>C) (8.1%), followed by Hb J-Paris-I [HBA2: c.38C>A (or HBA1)] and Hb Manitoba II (HBA1: c.309C>A) (7.4% for each). Other α variants were detected at lower frequencies. Two novel alleles were also detected: Hb Walsgrave [α116(GH4)Glu→Val (HBA2: c.350A>T)] and Hb Coombe Park [α127(H10)Lys→Glu (HBA2: c.382A>G)]. The majority of the ethnic origin was Indian. The positive predictive value for α variant identification by HPLC-RT analysis was 65.9%, 41.9% by IEF, and using both RT and IEF, the value was 72.1%. The number of variants was higher in HBA1 than in HBA2 genes and in exons 1 and 2 than in exon 3. There was no clustering of mutations in consecutive codons. This study, the characterization of a wide spectrum of α-globin chain variants, can facilitate the presumptive diagnosis of these variants prior to screening by a panel of amplification refractory mutation system-polymerase chain reaction (ARMS-PCR), and a definitive diagnosis by DNA sequencing.

Clinico-Hematological Profile of Hb Q India: An Uncommon Hemoglobin Variant

Inherited hemoglobin disorders include thalassemias and structural variants like HbS, HbE, and HbD, Hb Lepore, HbD-Iran, Hb-H disease and HbQ India. HbQ India is an uncommon alpha-chain structural hemoglobin variant seen in North and West India. Patients are mostly asymptomatic and often present in the heterozygous state or co-inherited with beta-thalassaemia. This study was done in a tertiary care teaching hospital in North India over a period of 7years among patients referred from antenatal and other clinics for screening of hemoglobin disorders. Complete blood count, peripheral blood smear examination and cation exchange high performance liquid chromatography (HPLC) was done to quantify various hemoglobins. HbQ India was diagnosed if the unknown variant hemoglobin was detected within the characteristic retention window. Of a total of 7530 patients screened, 31 (0.4%) were detected to have HbQ India. Of these, 25 (0.3%) patients had HbQ India trait and 6 (0.1%) patients had compound heterozygosity for HbQ India and Beta Thalassemia trait (HbQ India-BTT). All patients were clinically asymptomatic and were detected as part of the screening for hemoglobin disorders. Only two patients with HbQ India-BTT had hemoglobin less than 10g/dL. In 25 patients with HbQ India trait, HbQ ranged from 13.6 to 24.4% and in 6 patients with HbQ India-BTT, HbQ India ranged from 7.4 to 9.0%. HbQ India is an uncommon structural hemoglobin variant. Although asymptomatic, it may cause diagnostic difficulty in the compound heterozygous state with beta thalassemia. HPLC provides a rapid, accurate and reproducible method for screening of this condition to identify and counsel individuals.

Mass Spectrometry-Based Diagnosis of Hemoglobinopathies: A Potential Tool for the Screening of Genetic Disorder.

Hemoglobinopathies are caused by point mutation in globin gene that results in structural variant of hemoglobin. While 7% of world populations are carrier of hemoglobinopathies, the prevalence of the disease varies between 3 to 17% across different population groups in India. In a diagnostic laboratory, alkaline gel electrophoresis and cation exchange-based HPLC (CE-HPLC) are most widely used techniques for characterization of hemoglobin variants. In the above methods, the differential surface charge of hemoglobin molecule in variants is exploited for their characterization. Sometime, co-migration of variants in gel electrophoresis and co-elution or elution with unknown retention time in automated CE-HPLC might lead to ambiguity in the analysis of hemoglobinopathies. Under such circumstances, it is necessary to use other analytical methods that provide unambiguous results. Mass spectrometry-based proteomics approach and DNA sequence analysis are examples of such alternative methods. In the present study, liquid chromatography coupled to mass spectrometry has been used for three commonly observed variants in India, e.g., HbE, HbQ India and HbD Punjab that appeared with inappropriate results in the conventional analysis. A customized hemoglobin variant database has been used in the mass spectrometry-based analysis of those three variants. Mass spectrometry-based proteomics approach was used to analyze above variant sample accurately.

Scanning for α-Hemoglobin Variants by High-Resolution Melting Analysis.

Definitive detection of hemoglobin (Hb) variants requires DNA sequencing. High-resolution melting (HRM) analysis of polymerase chain reaction (PCR) amplicons was applied to detect and discriminate among uncommon α-Hb variants found in Thailand. Uncommon suspected α-Hb variants observed in Hb typing were identified by sequencing of DNA from whole blood samples. Three pairs of PCR primers covering the mutation regions in the three α-globin exons then were used for PCR coupled with difference in HRM analysis to subtract out the concomitant melting profile of the normal allele in the heterozygous state. DNA sequencing identified six heterozygous α-Hb variants, namely, Hb G-Waimanalo (HBA2: exon 2, codon 64 G>A), Hb J-Buda (HBA1: exon 2, codon 61 G>T), Hb Kurosaki (HBA2: exon 1; codon 7 A>G), Hb O-Indonesia (HBA1: exon 3 codon 116 G>A), Hb Q-India (HBA1:exon 2, codon 64 G>C), and Hb Q-Thailand (HBA1: exon 2 codon 74 G>C). Difference HRM analysis showed one temperature melting profile using exon 1 primer pair, four different profiles with exon 2 primer pair, and one profile with exon 3 primer pair. PCR-HRM analysis was effective in detecting and discriminating among single point mutations causing six uncommon α-Hb variants in heterozygous individuals. The method can be applied for routine screening due to its simplicity and relatively low cost.

An Intriguing High Performance Liquid Chromatogram of a Double Heterozygosity for Hb Q-India/Hb D-Punjab

Cation exchange high performance liquid chromatography (HPLC) is commonly utilized as the first method of screening for thalassemias and hemoglobinopathies worldwide. This method of diagnosis requires knowledge of the clinical background and complete blood counts as well as skill and experience in interpreting the sometimes complex results produced. An asymptomatic 27-year-old pregnant North Indian woman was found to have a highly unusual chromatographic pattern with multiple unexpected peaks during routine antenatal screening. Most concerning was a C-window peak as Hb C (HBB: c.19G>A) is rare in ethnic Asian Indian populations. Cellulose acetate electrophoresis at alkaline pH (8.6) and parental screening were performed. These revealed the correct diagnosis to be a double heterozygosity for Hb Q-India (HBA1: c.193G>C) (an uncommon asymptomatic α-globin chain variant) plus Hb D-Punjab (HBB: c.364G>C) (a β-globin chain variant that is common in this region and is asymptomatic in the heterozygous state). The unexpected C-window peak was the hybrid of the abnormal α-Q-India and β-D-Punjab globin chains. Another small peak was explained as a variant Hb A2 formed by the combination of α-Q-India and δ-globin chains. Hematopathologists should be cognizant of the complex pattern resulting from coinheritance of both α- and β-globin structural variants. Second-line testing and parental testing are invaluable in resolving unknown peaks, especially if rare or unexpected variants are being considered. Although both Hb Q-India and Hb D-Punjab are relatively common in northwestern India, to the best of our knowledge, only two recent reports describe a total of three cases of such diagnostically puzzling coinheritance.

Double heterozygous hemoglobin Q India/hemoglobin D Punjab hemoglobinopathy: Report of two rare cases

Cation exchange high performance liquid chromatography (CE HPLC) provides an excellent tool for accurate and reliable diagnosis of various hemoglobin (Hb) disorders. HbQ India is a rare alpha chain variant that usually presents in the heterozygous state. Its presence in double heterozygous state with HbD Punjab is extremely rare. The double heterozygosity for α and β chain variants leads to formation of abnormal heterodimer hybrids, which can lead to diagnostic dilemmas. We report two rare cases of double heterozygous HbQ India/HbD Punjab where the hybrid Hb was seen to elute at retention time similar to HbC on CE HPLC. The first case had unconjugated hyperbilirubinemia at presentation; while, the second case was asymptomatic.

Antenatal Screening for Identification of Couples for Prenatal Diagnosis of Severe Hemoglobinopathies in Surat, South Gujarat

Our aim was to identify couples at risk of having a homozygous or compound heterozygous child with a severe hemoglobinopathy by antenatal screening and prenatal diagnosis in Surat, South Gujarat. Pregnant women were screened for hemoglobinopathies by means of red cell indices, the solubility test, cellulose acetate electrophoresis tests, and confirmation by HPLC. Husbands of the pregnant women having hemoglobinopathies were counseled and screened for hemoglobinopathies. The couples at risk were again counseled and referred to the National Institute of Immunohematology, where mutations in parents and fetuses were identified by molecular analysis. After prenatal diagnosis, the continuing pregnancies were followed up and infants were tested at birth. Out of 3,009 women, 37.04, 52.6, and 10.3% were in the first, second, and third trimester of pregnancy, respectively. Among those having hemoglobinopathies, 102 (3.38%) had the β-thalassemia trait, 46 (1.5%) the Sickle cell trait, and 26 (0.86) had hemoglobin variants like Hb DPunjab, Hb E, Hb DIran, Hb QIndia, Hb JParis-I, and Hb OIndonesia. Out of the 14 couples at risk of having an affected child, 11 (78.5%) couples opted for prenatal diagnosis. Three fetuses had homozygous β-thalassemia and hence the pregnancies were terminated. Follow up of normal or heterozygous fetuses confirmed the diagnosis. During antenatal screening, we found many Hb variants of β and α globin chains. Late antenatal registration, non-cooperation of the husband for investigation, and refusal for prenatal diagnosis are the main hurdles in the hemoglobinopathy prevention program and awareness is necessary.

Comparison of Sebia Capillarys Flex capillary electrophoresis with the BioRad Variant II high pressure liquid chromatography in the evaluation of hemoglobinopathies

BackgroundThere are multiple biochemical screening techniques for assessing hemoglobinopathies. Here we compare a new instrument, the Sebia Capillarys Flex (capillary zone electrophoresis (CE)), with the BioRad Variant II (high pressure liquid chromatography (HPLC) in the evaluation of hemoglobinopathies. MethodsThis was a retrospective study using 174 whole blood samples encompassing the 5 most common (Hb A, A2′, S, C, and E) and 10 rare (Hb GPhilidelphia, D, H, Bart's, OArab, S/GPhilidelphia, Hasharoon, QIndia, NBaltimore, and Malmo) hemoglobin variants. An additional 126 samples were used to establish a CE reference interval for Hb A2. ResultsHb A measurements agreed well between the 2 methods (bias=−0.06;r=0.999). The agreement of Hb F was also very good (bias=−0.17; r=0.994). When samples with the highest Hb F concentration were excluded, agreement was less precise (bias=−0.44; r=0.811). When no variant was present, the Hb A2 concentrations showed excellent agreement (bias=0.00; r=0.994). Positive bias for Hb A2 is seen when Hb C is present using CE. The Hb A2 reference interval using CE was <3.2%. ConclusionThe Capillarys Flex is capable of identifying and quantifying hemoglobin species, consistent with existing HPLC methods.

A novel double heterozygous, HbD Punjab/HbQ India, hemoglobinopathy

Hemoglobinopathies and thalassemias together form the most common genetic disease in the world. Double heterozygosity, in which there is a hemoglobin variant, in both the α- and non-α globin chains, is very unusual. A novel double heterozygosity of the α chain variant HbQ India with the non-α chain HbD Punjab is described. The index case is a 39 year old female of Indian origin. HPLC analysis using the Bio Rad β thalassemia method and electrophoresis at both alkaline and acid pH were performed. HPLC shows four major bands and electrophoresis at alkaline pH shows 3 bands and 2 bands at acid pH. Both the HPLC and electrophoresis at alkaline and acid pH are consistent for the double heterozygous hemoglobin variants HbQ India and HbD Punjab. This is the first literature report of the double heterozygosity of HbQ India/HbD Punjab.

The first use of EaeI restriction enzyme in DNA diagnosis of Hb Q‐India

The α-chain variant Hb Q-India (c.193G>C) is caused by a point mutation GAC→CAC at codon 64 of the α1 globin gene and is clinically silent. Point mutations can be diagnosed easily by many simple polymerase chain reaction (PCR) techniques including PCR-restriction digest, but for Hb Q-India the restriction digest has never been described. In this work we aimed to develop a restriction enzyme digestion assay for DNA diagnosis of Hb Q-India, in order to increase the panel of restriction enzymes used in DNA diagnosis of haemoglobinopathies and also as a simple cheap alternative to the ARMS-PCR method. A restriction enzyme digestion assay was designed for diagnosis of Hb Q-India using the restriction enzyme EaeI enzyme as the Hb Q-India mutation abolishes the recognition site of this enzyme. Patients were screened for an abnormal haemoglobin by high performance liquid chromatography (HPLC) and those had an abnormal peak with a retention time between 4.7 and 4.8 minutes were selected for diagnosis at the molecular level. The α1 globin gene was amplified in 12 cases with a presumed diagnosis of Hb Q-India by HPLC and isoelectric focusing (IEF), and the amplified products were subjected to the EaeI digestion. All the 12 cases were diagnosed positive (100%) for Hb Q-India by the EaeI restriction enzyme digest. They were heterozygotes for the mutation. EaeI restriction enzyme digestion can be used as a simple and robust alternative method to ARMS-PCR for DNA diagnosis of Hb Q-India. The EaeI restriction enzyme can be added to the panel of restriction enzymes used in the DNA diagnosis of the abnormal Hb variants. Concomitant use of HPLC and IEF can be used efficiently for presumed diagnosis of this rare variant.

Spectrum of haemoglobinopathies diagnosed by cation exchange-HPLC & modulating effects of nutritional deficiency anaemias from north India.

Background & objectives:The usefulness of cation exchange high performance liquid chromatography (CE-HPLC) as a tool for detection of thalassaemia/haemoglobin variants was evaluated in a prospective study in a tertiary care centre in north India. We also tried to evaluate the effect of concurrent nutritional deficiency on the HPLC pattern in the local ethnic population.Methods:A total of 800 blood samples were analyzed on the Bio-Rad Variant HPLC system by β-thal short program. The retention times, proportion of the haemoglobin (%), and the peak characteristics for all haemoglobin fractions were recorded. Alkaline and acid haemoglobin electrophoresis was performed to document the identities of the haemoglobin variants, wherever necessary. Many cases were subjected to family studies for a definitive diagnosis.Results:Among 800 samples tested, 553 (69.1%) were found to have normal HPLC pattern. Apart from β- thalassaemia, nine additional variants were encountered; HbS (2.8%), HbE (2.5%) and HbD (1.1%) being the most common variants present. Other variants included Hb Q-India, Hb-Lepore, δβ-thalassemia/ HPFH, HbD-Iran, HbJ-Meerut and HbH disease. There was a significant decrease in the level of HbA2 associated with iron deficiency anaemia (IDA) (P=0.004) and increase in megaloblastic anaemia (P<0.001) among subjects with normal HPLC pattern.Interpretation & conclusions:HPLC was found to be a simple, rapid and reliable method for the detection of hemoglobin variants. An accurate diagnosis can be provided in majority of cases by use of retention time, proportion of total haemoglobin, and peak characteristics of HPLC. Haemoglobin electrophoresis and family studies play a valuable role in difficult cases. Concurrent nutritional deficiency also has an effect on HbA2 levels.

Comparative analysis of protein structure of common Hb Q variants

Hemoglobin (Hb) Q variant is a group of hemoglobinopathies prevalent in south, south-east and western Asia. The primary structure of all of these molecules is well known. However, very little is known about the secondary and tertiary structures of these molecules. Therefore, a study of their secondary and tertiary structures is needed. The study was aimed at investigating the secondary and tertiary structures of common Hb Q variants using bioinformatics tool. The secondary and tertiary structures of common Hb Q variants were evaluated using NNPREDICT server and CPHmodels 2.0 server, respectively. Amino acid sequence of alpha globin chain was searched using ExPASY and was used for further mutation to Hb Q variants. The derived sequences were further analyzed using NNPREDICT server and CPHmodels 2.0 server to calculate their secondary and tertiary structures, respectively. These were then compared and any differences noted. It was observed that there is no difference between the predicted secondary structures of normal alpha globin and Hb Q-India. Hb Q-Iran carries an extra helix while Hb Q-Thailand carries two extra helices. The results of tertiary structure prediction also support these findings. Differences in secondary and tertiary structure of various Hb Q variants have been observed in the present study. The study provides valuable data for better understanding of these uncommon hemoglobinopathies.

Electrospray mass spectrometric characterization of hemoglobin Q (Hb Q-India) and a double mutant hemoglobin S/D in clinical samples

Objectives: The clinical analysis of hemoglobin by ion exchange chromatography can result in ambiguities in identification of the nature of the globin chain present in patient samples. LC/ESI-MS provides rapid and precise determination of globin chain masses. Design and methods: Hemolysate of hemoglobin Q-India and hemoglobin S/D/F have been analyzed using ESI-MS. Tandem-MS has been used to establish mutation in α chain of hemoglobin Q. Results: The identification of hemoglobin Q-India is readily achieved by LC/ESI-MS, which establishes the presence of a mutant α chain differing in mass from normal α chain by 22 Da. The site of mutation has been identified by tandem-MS analysis of a tryptic fragment encompassing residues αV62-K90. LC/ESI-MS screening has also provide an example of simultaneous occurrence of mutant globin chains containing β6E → V (Hb S, sickle) and β121E → Q (Hb D) variant. Expression of γ G globin chain is also demonstrated in this sample. Conclusions: The site of mutation in hemoglobin Q-India is identified as α64D → H which differs from mutations α74D → H in Hb Q-Thailand and α75D → H in Hb Q-Iran. Mass spectrometric analysis of hemoglobins from a patient and her parents suggests inheritance of mutant β globin genes from both parents.

Hb QIndia and its interaction with β–thalassaemia: a study of 64 cases from India

Haemoglobin Q (Hb Q), a relatively uncommon α-chain structural Hb variant, has been reported either in the heterozygous state or interacting with β-thalassaemia. Individuals inheriting Hb Q generally are asymptomatic and are diagnosed by chance during population screening or as a part of a family study. This paper represents the first large study from India of 64 cases of Hb Q, documenting the haematological and molecular findings on 36 cases of Hb Q trait, 22 of Hb Q β-thalassaemia trait and three of Hb Q β-thalassaemia major, as well as a family of Hb Q homozygous cases. Hb Q is detected by Hb electrophoresis and chromatography. Hb Q levels in homozygous cases ranged from 32% to 35%, while in Hb Q heterozygotes the level was 20%. When there was an interaction of β-thalassaemia heterozygotes the level was 14%, and in interacting β-thalassaemia homozygotes the levels range from 7% to 9%. β-thalassaemia mutations were characterised in cases showing elevated Hb A2 levels, which were markedly reduced in the majority of cases in which β-thalassaemia was absent. Hb Q is rare and not a single homozygous case has been reported. However, Hb Q disease showed wide variation in clinical and haematological presentation in the same family.

A Rare Case Of Co-Existent Hb Q India-Beta Thalassemia Trait

Hb QIndia is a rare alpha chain variant and usually it presents in the heterozygous state. It's presence along with beta thalassemia trait again adds to its rarity. Such a rare entity can be diagnosed by careful screening in routine practice with the use of the techniques like Hb electrophoresis, Solubility test. We report a case of Hb Q in a concomitant presence of Beta thalassemia trait. CASE REPORT A 19 years old boy presented to us for the screening of the beta thalassemia minor and was found to have variant hemoglobin migrating in the position of the Hemoglobin S (HbS) on cellulose acetate electrophoresis at alkaline pH. The patient was asymptomatic without any significant past or family history and clinical examination. Automated cell counter used to determine the cell counts and indices showed the presence of thalassemic indices, whereas solubility test for sickling was negative (Table-1). Suspecting the presence of beta thalassemia trait, Hb electrophoresis at pH 8.4 was performed which showed presence of an abnormal band in the position of Hb S and duplicated bands of Hb A2 apart from normal band of Hb A, suggesting the presence of alpha chain variant in heterozygous state (Figure-1). Figure 1 Figure 1: Photograph showing the electrophoretic mobility of hemoglobin at pH 8.4 in propositus, father, mother, sister, and control of a known case of sickle cell trait. A Rare Case Of Co-Existent Hb Q India-Beta Thalassemia Trait 2 of 4 Figure 2 Table 1 Microcolumn chromatography using glycine-potassium cyanide developers showed the presence of high levels of Hb A2 in the thalassemic range (Table-2).

Identification of Hb Q-India (64 Asp→His) in Thailand

More than 30 different hemoglobin variants either affecting  or β globin chains have been identified in Thailand. The large variety in the different forms of hemoglobinopathy contributes to several complicated interactions, since different types of defective globin alleles are prevalent in Thailand and nearly 30-40% of the population are carriers of either  or β thalassemia (thal). Many rare and novel abnormal globin variants in Thai subjects have been identified in our laboratory within the past few years; including Hb Lepore-Hollandia, homozygous Hb Tak, Hb Dhonburi, Hb G-Makassar, Hb G-Coushatta, Hb New York, Hb Paksè and Hb Pak Num Po. In addition to these, here we report, for the first time, the identification of Hb Q-India, an innocuous  globin variant, in a Thai family with Indian ancestry. This report highlights the complexity associated with identifying unknown globin variants within a population that has a heterogeneous repertoire of globin chain disorders.

Hb Q-India: an uncommon variant diagnosed in three Punjabi patients with diabetes is identified by a novel DNA analysis test

Aims: An abnormality in the glycated haemoglobin peak (Hb A1c) on Diastat (Bio-Rad) cation exchange low pressure liquid chromatography (LPLC) was found in three Punjabi patients with diabetes. The aims...