Thalassemia in India.

Management and control of hemoglobinopathies are a challenge in India where 67.0% of people reside in rural regions. The GDP spent on health is one of the lowest (1.3%) resulting in high out-of-pocket expenses. The ß-thalassemias are prevalent with an estimated 7500-12000 new births each year. Hb S (HBB: c.20A>T) and Hb E (HBB: c.79G>A) are also common regionally. Over 80 ß-thalassemia (ß-thal) mutations have been characterized in Indians. The δ gene mutations are increasingly being described and their coinheritance in ß-thal carriers leads to a reduction in Hb A2 levels and a misdiagnosis of carriers. Around 15-20 centers offer prenatal diagnosis (PND) mainly in urban regions. The projected annual cost of care of ß-thal patients over a decade (2016-2026) will increase from INR30,000 (US$448) million to INR55,000 (US$820) million if all patients are adequately treated. Cost comparisons are difficult to make with other international studies as the standard of care, cost of medicines and other services vary in different countries. Several centers provide hematopoietic stem cell transplants (HSCTs) for thalassemias, however, only around 250 HSCTs are done annually. Although the cost is high, financial assistance is available for a few patients. There are disparities in the quality of care and to address this a National Policy has been proposed for the management and prevention of hemoglobinopathies that will embark on a comprehensive program, providing adequate care and augmenting the existing public health care services. It will also include training, genetic counseling and easier access to preventive options and a National Registry.

Spectrum of ß-Thalassemia and Other Hemoglobinopathies in the Saurashtra Region of Gujarat, India: Analysis of a Large Population Screening Program.

Hemoglobinopathies are common genetic disorders of the hemoglobin (Hb) molecule. Globally, 7.0% of the population are carriers of thalassemia with 300,000-400,000 affected births each year. There are >40 million carriers of ß-thalassemia (ß-thal) in India with 10,000-12,000 affected births every year. This makes control programs crucial in this vast and diverse country. The present study was undertaken to find out the burden of hemoglobinopathies, and in particular, the prevalence of ß-thal carriers in the population of Saurashtra region of Gujarat in Western India. A total of 16,780 individuals, including school and college students, were screened. Complete blood counts (CBCs) and high performance liquid chromatography (HPLC) analysis were performed. We detected 1891 (11.26%) individuals with different hemoglobinopathies, of whom 758 (4.52%) were diagnosed to carry ß-thal trait, 104 (0.62%) carried Hb D-Punjab (HBB: c.364G>C) trait, 61 (0.36%) carried sickle cell trait, 32 (0.19%) carried δß-thal trait/HPFH (hereditary persistence of fetal Hb) trait, and other hemoglobinopathies were identified in smaller numbers (0.15%). We encountered 27 individuals with mean corpuscular Hb (MCH) <27.0 pg and mean corpuscular volume (MCV) <80.0 fL levels, who had borderline Hb A2 levels (3.2-3.5%). Twenty castes showed the presence of ß-thal or other hemoglobinopathies. A high prevalence of ß-thal was found in the Sindhis (11.67%), Lohanas (9.71%), Brahmins (6.31%), Bharvads (6.94%), Harijans (7.57%) and Vankars (7.77%). All the heterozygotes were given appropriate counseling. A multi pronged approach, including screening of high school and college students, needs to be considered for this vast and ethnically diverse country to reduce the burden of hemoglobinopathies.

Role of Oxidative Stress and the Protective Effect of Fermented Papaya Preparation in Sickle Cell Disease.

Fermented papaya preparation (FPP) is the source of antioxidants that may help in reducing the complications associated with oxidative stress and may improve the quality of life in sickle cell disease patients. In this study, we assessed the in vitro effect of FPP on sickled red blood cells (RBCs) using oxidative stress markers and observed that FPP has the potential to reduce the oxidative stress. Scanning electron microscopy (SEM) and eosin 5' malaemide (E5'M) dye test showed that FPP protects red cell morphology against the oxidative stress. Liquid chromatography mass spectrometry (LCMS) analysis of FPP suggests the presence of essential amino acids, vitamin D3, and its derivatives. Fermented papaya preparation can be of benefit either in reducing oxidative stress parameters or in preventing pathophysiological events in the sickle cell disease patients.

The Changing Trends in Prenatal Diagnosis of Hemoglobinopathies in India: The Quest of a Single Center to Reduce the Burden of Disease over Three Decades.

The ß-thalassemias and sickle cell disorders pose a considerable health burden in India. Of the more than 10,000 annual births of children with a severe hemoglobinopathy, only around 10.0% are managed optimally. Thus, genetic counseling and prenatal diagnosis (PND) is a valid option for a large and diverse country. Our center was one of the first to initiate PND and we present our experience over 30 years to evaluate the impact of awareness in changing the trends of PND of hemoglobinopathies. Both second and first-trimester diagnoses were undertaken by fetoscopy/cordocentesis and globin biosynthesis/high-performance liquid chromatography (HPLC) analysis of fetal blood and chorionic villus sampling (CVS) and DNA analysis. Over 30 years, 3478 couples (first trimester: 2475; second trimester: 1003) from all over India were offered PND. The number of couples coming in the first trimester increased significantly over each decade and couples coming prospectively increased from 2.5 to 18.4%. A cost-effective stepwise approach was used for molecular analysis. Eight hundred and one fetuses (23.0%) were affected and all except three couples opted for termination of these pregnancies. Genetic counseling and PND is the only way to reduce the burden of disease. With awareness, there was a shift from second trimester to first trimester PND over each decade, with an increasing number of couples coming during the first pregnancy. There are only 15 to 20 centers in India offering PND. We have compared our study with other reports on PND from different regions in India.

Red Cell Distribution Width (RDW): Normative Data in Indian Neonates.

Red cell distribution width (RDW) is altered because of prematurity and fetal growth restriction (FGR). We conducted a prospective observational study to determine normal RDW values in Indian neonates (N=964) with significant FGR. Mean RDW values in preterm neonates were higher than term neonates (P<0.0004). The RDW values in Indian neonates (with significant FGR) were higher than their western counterparts (P<0.0001). The mean RDW values for different gestational ages in Indian neonates are higher than those observed in other studies. This could be attributable to the FGR component among Indian neonates.

Genetic lesions in the UGT1A1 genes among Gilbert's syndrome patients from India.

The present study was undertaken to investigate genetic variations present in the coding regions of the UGT1A1 gene among the Gilbert's syndrome patients. Analysis of genetic variations was performed by direct DNA sequencing among the patients that do not have any polymorphic variations in the promoter regions of the UGT1A1 gene. We identified seven different sequence variations among Gilbert's Syndrome patients, of which four were novel. Out of seven variants, six missense and one silent single nucleotide substitutions were present in the UGT1A1 gene. In addition, molecular modeling of UGT1A1 (H55R, P152S and N212H) variants suggested a reduced activity of the enzyme. This study demonstrates that different variations present in the UGT1A1 gene and specifically, the H55R variation had a significant effect on bilirubin levels and could be genetic risk factors for hyperbilirubinemia.

Newborn Screening for Hemoglobinopathies and Red Cell Enzymopathies in Tripura State: A Malaria-Endemic State in Northeast India.

Hemoglobinopathies are a group of inherited single gene disorders. There are reports on hemoglobin (Hb) variants identified in the tribal and non-tribal populations of Tripura State in northeastern India. This study aimed to determine the spectrum of hemoglobinopathies and enzymopathies by newborn screening in Tripura State and assess the extent of neonatal jaundice. A total of 2400 cord blood samples were collected and analyzed by high performance liquid chromatography (HPLC). Further confirmation of any abnormal HPLC was done by DNA analysis. The samples were also screened for deficiency of enzymopathies, glucose-6-phosphate dehydrogenase (G6PD) deficiency and pyruvate kinase. Of 2400 cord blood samples screened, 225 (9.3%) were Hb E (HBB: c.79G>A) heterozygotes, 80 (3.3%) were Hb E homozygotes and one carried Hb E-ß-thalassemia (ß-thal). Other Hb abnormalities were also detected including 15 Hb S (HBB: c.20A>T) heterozygotes, two Hb D-Punjab (HBB: c.364G>C) heterozygotes and two compound heterozygotes for Hb D-Punjab and Hb E. Of the 80 homozygous Hb E babies, four were non-tribal and 76 babies were tribal, and 225 patients carried Hb E trait, 141 were tribal, while 84 were non-tribal. Of 40 G6PD deficient babies identified, 13 had coinherited Hb E and two babies had pyruvate kinase deficiency. α Genotyping was performed in 162 affected babies, 50 of them carried α gene deletions. Newborn screening programs for Hb E, other hemoglobinopathies and G6PD deficiency must be encouraged in the malaria-endemic northeastern region of India. Drug-induced hemolysis can also be avoided by screening for G6PD deficiency at birth.

Rare ß- and δ-Globin Gene Mutations in the Pathare Prabhus: Original Inhabitants of Mumbai, India.

Genetic structure of the Indian population is influenced by waves of several immigrants from West Eurasia. Therefore, genetic information of various ethnic groups is valuable to understand their origins, the pattern of migration as well as the genetic relationship between them. No genetic data is available on Pathare Prabhu, which is a small indigenous Hindu community from Mumbai, Maharashtra State, India. The aim of this study was to screen the Pathare Prabhus for hemoglobinopathies, which is a major public health problem in India. Two hundred and fifty-seven unrelated Pathare Prabhus subjects were screened for various hemoglobinopathies. Complete blood counts (CBC) were done on an automated hematology counter. High performance liquid chromatography (HPLC) was used to identify ß-thalassemia (ß-thal) carriers. Molecular characterization of the ß gene defects was done by reverse dot-blot hybridization, amplification refractory mutation system (ARMS) and DNA sequencing. Deletional α-thalassemia (α-thal) was detected by multiplex polymerase chain reaction (PCR). Hb A2-Saurashtra (HBD: c.301C>T) was identified by DNA sequencing; its modeling was also done. The prevalence of ß-thal was 3.89%, while deletional α-thal was 5.4%. The initiation codon (ATG>ACG) (HBB: c.2T>C) was seen in eight individuals (80.0%), Hb D-Punjab (HBB: c.364G>C) and Hb A2-Saurashtra, was found in two and one individual, respectively. A community-specific ß-thal mutation was found in Pathare Prabhus in significant proportions. This information is useful in developing an algorithm for a prenatal diagnosis (PND) program.

Genetic Variations in Bilirubin Metabolism Genes and Their Association with Unconjugated Hyperbilirubinemia in Adults.

OBJECTIVE: The present study was undertaken to investigate the genotype and allele frequencies of the variants in the four bilirubin metabolism genes (UGT1A1, OATP2, HMOX1, and BLVRA) and their association with hyperbilirubinemia. MATERIAL AND METHODS: Genotyping of 17 genetic variants was performed in 115 adults with hyperbilirubinemia and 150 controls by PCR-RFLP, GeneScan analysis, and direct DNA sequencing. RESULTS: Genetic polymorphisms of the UGT1A1 promoter, specifically the T-3279G phenobarbital-responsive enhancer module and (TA)7 dinucleotide repeat, as well as the intron and coding region variants of the OATP2, HMOX1, and BLVRA genes, were significantly higher among the cases than the controls. Further, nearly 82% of the cases showed the presence of significantly four or more variants as compared to 37% of the controls (P < 0.0001) and the mean total serum bilirubin levels also increased according to the number of variants co-expressed. CONCLUSIONS: This study demonstrates that polymorphisms in the bilirubin metabolism genes had a significant effect on bilirubin levels and could be genetic risk factors for hyperbilirubinemia.

Effect of the Hemochromatosis Mutations on Iron Overload among the Indian ß Thalassemia Carriers.

BACKGROUND: Hereditary hemochromatosis is a disorder of iron metabolism characterized by increased iron absorption.HFE gene mutations C282Y and H63D are responsible for the majority of hereditary hemochromatosis cases. METHODS: We tried to look at the effect of HFE mutations on the iron status. A total of 100 ß thalassemia traits (BTT) with 100 normal individuals were screened for the C282Y and H63D mutations using PCR-RFLP. The serum ferritin levels were determined using ELISA kit. RESULTS: We did not find the C282Y mutation in our study group. The allelic frequencies for H63D mutation did not differ significantly between ß-thalassemia traits (8.5%) and normal controls (9%). ΒΤΤ with H63D genotype of H/D (143.16 ± 80.3 ng/ml) and D/D (504 ng/ml) showed higher ferritin levels as against H/H genotype (88.64 ± 92.43 ng/ml). The statistically significant difference was observed in the mean serum ferritin levels among the individuals showing H/H and D/D genotypes (P < 0.002) and H/D and D/D genotype (P < 0.01) in both the groups. CONCLUSION: This suggests that iron load in BTT tends to aggravated with the co-inheritance of the H63D mutation. The mutant H63D gene showed the presence of haplotype 6 which is reported in the European population suggesting a common origin.

Hb E-ß-Thalassemia in Five Indian States.

Hb E [ß26(B8)Glu→Lys; HBB: c.79G > A]-ß-thalassemia (ß-thal) has an extremely variable clinical presentation. We report the clinical features of these patients from five Indian states together with their hematological and molecular characteristics. Seventy-eight Hb E-ß-thal patients from different regions [West Bengal (30), Maharashtra (21), Uttar Pradesh (13), Bihar (11), Orissa (3)] were clinically evaluated along with hematological profiles and molecular characteristics (ß-thal mutations, XmnI polymorphisms, α genotypes). Twenty-nine of the 78 patients had a mild clinical presentation (clinical score 2.2 ± 1.1), while 15 had moderate severity (clinical score 6.1 ± 1.2) with occasional transfusion needs, and 34 patients were severely affected (clinical score 8.2 ± 0.5) requiring regular blood transfusions. The age at clinical presentation in the severely affected patients was lower (6 months-10 years) as compared to those with milder symptoms (2 years-34 years). Thirty-four patients showed splenomegaly (spleen ≥3 cm below the costal margin) and five patients were splenectomized. The severe ß+ IVS1-5 (G > C) (HBB: c.92 + 5G > C) was the most common ß-thal mutation, while seven other mutations were also seen. The XmnI [+/+] and [-/-] polymorphisms were seen in 24.1 and 10.3% of mildly affected patients and 14.7 and 17.6% of severely affected patients respectively. A single α gene deletion (-α3.7/αα) was found in 20.7% of mildly affected and 5.9% of severely affected patients, respectively. No specific differences in the clinical, hematological or molecular characteristics were observed in the Hb E-ß-thal patients from various geographic regions or different ethnic groups.

Diverse phenotypes and transfusion requirements due to interaction of ß-thalassemias with triplicated α-globin genes.

Co-inheritance of triplicated α-genes can alter the clinical and hematological phenotypes of ß-thalassemias. We evaluated the phenotypic diversity and transfusion requirements in ß-thalassemia heterozygotes, homozygotes, and normal individuals with associated α-gene triplication. Clinical and hematological evaluation was done and the ß-thalassemia mutations characterized by a covalent reverse dot blot hybridization/amplification refractory mutation system. Alpha-globin gene triplication was assessed by multiplex PCR. During the last 2.5 years, 181 ß-thalassemia patients and ß-thalassemia carriers with an unusual clinical presentation were referred to us for screening for the presence of associated α-globin gene triplication. Twenty-nine of them had associated α-gene triplication (3 ß-thalassemia homozygotes or compound heterozygotes and 26 ß-thalassemia heterozygotes). One ß-thalassemia compound heterozygote [IVS 1-5 (G → C) + CD 41/42 (-CTTT)] was anemic at birth and required blood transfusions unusually early by 6 weeks of age. The second patient (4.5 years) was also clinically severe and became transfusion dependent in spite of having one mild ß-thalassemia mutation [Capsite +1 (A → C)]. The third case (3.5 years) who was homozygous for a mild ß-gene mutation [-88 (C → T)] with α gene triplication was untransfused. The 26 ß-thalassemia heterozygotes with associated triplicated α-genes presented variably, with a ß-thalassemia intermedia-like presentation. While screening the family members of all these cases, we found another 10 ß-thalassemia heterozygotes and 9 normal individuals with α-globin gene triplication; however, all of them were asymptomatic. Beta-thalassemia carriers, homozygotes, and compound heterozygotes with an unusual presentation should be screened for the possible presence of associated α-globin gene triplication which could influence the clinical and hematological presentation.

Haemoglobinopathies in tribal populations of India.

Haemoglobinopathies particularly haemoglobin S and E (HbS, HbE) and ß-thalassaemia are important challenges for tribal populations in India. The HbS, HbE and ß-thalassaemia genes are variably distributed across various tribal populations of India. HbE is mainly restricted in tribals of North-East, West Bengal, Odisha and those in Andaman and Nicobar islands. HbS has more extensive distribution in the country (10-40% trait frequency) and the homozygotes and double heterozygotes present with a wide array of morbidities. The morbidity varies greatly in different areas of the country due to differential co-inheritance of α-thalassaemia gene and interaction of various epistatic and environmental factors. Though substantial data on prevalence of these disorders exist, there is an urgent need to develop integrated hierarchical core facilities to manage the disease. Such centres will generate more data and will also explore areas of management which need more local attention. Newborn screening, genetic counselling, carrier detection, prenatal diagnosis along with management of cases should form the basic infrastructure of haemoglobinopathy management. Research in this areas should continue focusing on various challenges in care delivery, prevention and basic sciences on interaction of haemoglobinopathies with various other infections.

Sickle cell disease in tribal populations in India.

The sickle gene is widespread among many tribal population groups in India with prevalence of heterozygotes varying from 1-40 per cent. Co-inheritance of the sickle gene with ß-thalassaemia, HbD Punjab and glucose-6-phosphate dehydrogenase (G6PD) deficiency has also been reported. Most of the screening programmes in India now use high performance liquid chromatography (HPLC) analysis although the solubility test is also sensitive and cheap. Sickle cell disease (SCD) among tribal populations is generally milder than among non-tribal groups with fewer episodes of painful crises, infections, acute chest syndrome and need for hospitalization. This has partly been attributed to the very high prevalence of α-thalassaemia among these tribes as well as higher foetal haemoglobin levels. However, the clinical presentation is variable with many cases having a severe presentation. There is not much information available on maternal and perinatal outcome in tribal women with sickle cell disease. Newborn screening programmes for SCD have recently been initiated in Maharashtra, Gujarat, Orissa and Chattisgarh and monitoring these birth cohorts will help to understand the natural history of SCD in India. Prenatal diagnosis is acceptable by tribal families in India. The Indian Council of Medical Research and the National Rural Health Mission in different States are undertaking outreach programmes for better management and control of the disease.

Glucose-6-phosphate dehydrogenase (G6PD) deficiency among tribal populations of India - Country scenario.

It is believed that the tribal people, who constitute 8.6 per cent of the total population (2011 census of India), are the original inhabitants of India. Glucose-6-phosphate-dehydrogenase (G6PD) deficiency is an X-linked genetic defect, affecting around 400 million people worldwide and is characterized by considerable biochemical and molecular heterogeneity. Deficiency of this enzyme is highly polymorphic in those areas where malaria is/has been endemic. G6PD deficiency was reported from India more than 50 years ago. t0 he prevalence varies from 2.3 to 27.0 per cent with an overall prevalence of 7.7 per cent in different tribal groups. Since the tribal populations live in remote areas where malaria is/has been endemic, irrational use of antimalarial drugs could result in an increased number of cases with drug induced haemolysis. Therefore, before giving antimalarial therapy, routine screening for G6PD deficiency should be undertaken in those tribal communities where its prevalence is high.

Newborn screening for haemoglobinopathies by high performance liquid chromatography (HPLC): diagnostic utility of different approaches in resource-poor settings.

BACKGROUND: Sickle cell disease is a major health burden in India. The aim of the study was to compare the diagnostic utility of two different approaches on automated high performance liquid chromatography (HPLC) for newborn screening for sickle cell disorders and other haemoglobinopathies in India. METHODS: Newborn babies of sickle heterozygous mothers were tested by HPLC using two different kits, the ß-thal short kit, which is routinely used for screening for haemoglobinopathies in most laboratories, and the sickle cell short kit which is specific only for neonatal samples. Confirmation of the sickle and α genotypes was done by molecular analysis. RESULTS: Of the 601 babies tested, 276 were normal, 284 were sickle heterozygous and 41 were sickle homozygous using the ß-thal short kit. Using the sickle cell short kit, a discrepancy was seen in one newborn sample where a normal baby was identified as a sickle heterozygous baby. α-Genotyping was done in 42 babies and 16 of them had α gene deletions. The presence of α thalassaemia could be suspected in 15 of these 16 babies based on a spike at the start of the chromatogram using the ß-thal short kit. In comparison, using the sickle cell short kit the diagnosis of α thalassaemia was difficult based on the percentage of the FAST peak. Further, other rare α chain Hb variants were also missed. CONCLUSIONS: The ß-thal short kit was more versatile than the sickle cell short kit for screening for haemoglobinopathies in newborns in our population.

Masking of a ß-thalassemia determinant by a novel δ-globin gene defect [Hb A2-Saurashtra or δ100(G2)Pro→Ser; HBD: c.301C>T] in Cis.

Abstract The molecular basis of ß-thalassemia (ß-thal) syndromes have been well documented, while the spectrum of mutations causing δ-thalassemia (δ-thal) has not been well characterized. δ-Thalassemia has no clinical symptoms but its coinheritance with heterozygous ß-thal may cause misdiagnosis, especially in countries with a high prevalence of ß-thal where prevention programs have been implemented. The coinheritance of ß- and δ-globin mutations in India is not common. This association may interfere with correct diagnosis and genetic counseling of ß-thal in screening programs. Here we report two families showing borderline Hb A2 levels belonging to the Koli Community, indigenous to the Saurashtra Province of Gujarat, India. They were referred to us for thalassemia molecular screening as they had children clinically presenting before 2 years of age and requiring regular blood transfusions. Interestingly, both families carried a novel δ-globin gene mutation at codon 100 (C > T) linked to a polyadenylation (polyA) site [AATAAA > A(-AATAA)] 5 bp deletional ß-thal mutation, never before reported in the Indian population. This report highlights the importance of considering δ-globin gene analysis during ß-thal screening to avoid false-negative results in the detection of at-risk couples. It also highlights how incomplete diagnosis of a borderline or normal Hb A2 level may lead to the probable birth of a ß-thal major (ß-TM) child. This has important implications in prenatal diagnosis.

Interaction of iron deficiency anemia and hemoglobinopathies among college students and pregnant women: a multi center evaluation in India.

Although iron deficiency anemia is very common in India, systematic large studies on the prevalence and hematological consequences of iron deficiency among carriers of ß-thalassemia (ß-thal) and other hemoglobinopathies are lacking. A multi center project was undertaken to screen college/university students and pregnant women for iron deficiency anemia and various hemoglobinopathies. Fifty-six thousand, seven hundred and seventy-two subjects from six states, Maharashtra, Gujarat, Karnataka, West Bengal, Assam and Punjab, were studied. Iron deficiency anemia was evaluated by measuring zinc protoporphyrin (ZPP) and hemoglobin (Hb) levels, while ß-thal and other hemoglobinopathies were detected by measuring the red cell indices and by Hb analysis using high performance liquid chromatography (HPLC). College boys (2.2%), college girls (14.3%) and antenatal women (27.0%) without any hemoglobinopathies had iron deficiency anemia. Among the ß-thal carriers, the prevalence of iron deficiency anemia was 17.3% in college boys, 38.1% in college girls and 55.9% in pregnant women, while in the Hb E [ß26(B8)Glu→Lys; HBB: c.79G>A] carriers, it was 7.3% in college boys, 25.4% in college girls and 78.0% in antenatal women. In individuals with Hb E disease, the prevalence of iron deficiency anemia varied from 31.2-77.3% in the three groups. A significant reduction in Hb levels was seen when iron deficiency anemia was associated with hemoglobinopathies. However, the Hb A2 levels in ß-thal carriers were not greatly reduced in the presence of iron deficiency anemia.

Wide spectrum of novel and rare hemoglobin variants in the multi-ethnic Indian population: A review.

The hemoglobin (Hb) variants are qualitative abnormalities due to production of structurally abnormal globin proteins. They are categorized based on the type of mutation present in the α1, α2, ß, Gγ, Aγ and δ globin genes. So far, more than 1550 Hb variants are reported in the database. They could lead to Hb polymerization, Hb instability, altered oxygen affinity and decreased oxygen-carrying capacity of Hb or have no clinical manifestations. In India, ethnic diversity, consanguinity, regional variations and migration result in the presence of different Hb variants. We have compiled all the variants of α, ß and δ globin chains in heterozygous, homozygous and in compound heterozygous forms reported from India in the last 52 years. Of the 63 rare and novel hemoglobin variants reported from India, 22 were α-globin chain variants, 37 were ß-globin chain variants and 4 were δ-globin chain variants. Twelve novel Hb variants (Hb J Rajappan, Hb Koya Dora, Hb Rampa, Hb Godavari, Hb Chandigarh, Hb D Agri, Hb Lucknow, Hb Vellore, Hb Midnapore, Hb Bijnor, Hb A2Tianhe and Hb A2Saurashtra) were identified among persons of Indian origin. Majority of them were picked up on HPLC. Some of the variants like Hb Titusville, Hb Shimonoseki, Hb Chandigarh, Hb D Agri, Hb Yaizu and Hb Vellore eluted in the HbS window whereas variants like HbD Iran, Hb St. Louis, Hb G Coushata, HbM Saskatoon, Hb Lucknow, Hb Grange-Blanche and Hb Tianshui showed falsely elevated HbA2. Hence, careful and systematic investigations are required to identify them.

Effect of a group of genetic markers around the 5' regulatory regions of the ß globin gene cluster linked to high HbF on the clinical severity of ß thalassemia.

The clinical and hematological course of ß thalassemia intermedia is influenced by a number of genetic factors which play a role in increasing fetal haemoglobin levels. Several polymorphisms located in the promoters of ß and γ globin gene are involved in influencing the disease severity. Our objective was to study the effect of cis-DNA haplotypes, motifs, or polymorphisms (Pre G γ globin gene haplotypes, Aγ-δ intergenic region haplotypes XmnI and (AT)(x)(T)(y) polymorphisms, ß-LCR HS2 and HS3 site motifs) that may contribute to higher HbF levels and a milder clinical course. We found that a combination of T haplotype of the Aγ-δ intergenic region, TAG Pre-Gγ haplotype, presence of the XmnI polymorphism along with the (AT)(9)(T)(5) motif constitutes a topography that co-relates with raised HbF levels which may contribute in ameliorating the disease severity.