Carbonyl reductase 1 expression influences daunorubicin metabolism in acute myeloid leukemia.

PURPOSE: The present study aimed to investigate the role of expression of daunorubicin-metabolizing enzymes carbonyl reductase 1 and 3 (CBR1 and CBR3) on the in vitro cytotoxicity of daunorubicin in primary acute myeloid leukemia (AML) cells and the effect of genetic variants in CBR1 and CBR3 on the plasma pharmacokinetics of daunorubicin and daunorubicinol (DOL) in AML patients. METHODS: RNA expression of CBR1 and CBR3, intracellular daunorubicin and DOL levels, and in vitro cytotoxicity of daunorubicin were measured in bone marrow mononuclear cells of 104 adult AML patients. Plasma pharmacokinetics of daunorubicin and DOL was measured in 24 patients receiving daunorubicin-based induction chemotherapy for AML. RESULTS: Increased expression of CBR1 significantly reduced the in vitro cytotoxicity of daunorubicin and also positively correlated with intracellular DOL levels. Polymorphisms in CBR1 and CBR3 did not show any association with intracellular daunorubicin or DOL levels, but there was a trend towards significant increase in plasma daunorubicin systemic exposure in patients with a variant genotype for CBR1 polymorphism rs25678. CONCLUSIONS: This pilot study suggests that CBR1 RNA expression may be helpful in identifying AML patients at risk of developing resistance or toxicity to daunorubicin due to increased formation of DOL. Further confirmation of these findings in a larger sample pool would be required to determine the applicability of these results. Inhibition of CBR1 can be an option to improve the efficacy and prevent toxicity related to the treatment. Influence of daunorubicin and DOL plasma levels on clinical outcome, if any, remains to be evaluated.

Polymorphism in factor VII gene modifies phenotype of severe haemophilia.

The basis for 10-15% of patients with severe haemophilia having clinically mild disease is not fully understood. We hypothesized that polymorphisms in various coagulant factors may affect frequency of bleeding while functionally significant polymorphisms in inflammatory and immunoregulatory genes may also contribute to variations in the extent of joint damage. These variables were studied in patients with severe haemophilia, who were categorized as 'mild' (<5 bleeds in the preceding year, <10 World Federation of Haemophilia clinical and <10 Pettersson scores, n = 14) or 'severe' (all others, n = 100). A total of 53 parameters were studied in each individual for their association with the clinical severity. Age, F8:c activity and the incidence of thrombotic markers were comparable between the groups while the median number of bleeds, number of affected joints, clinical, radiological and functional joint scores (P < or = 0.001) and life-time clotting factor use (P < or = 0.007) were different. Patients with severe molecular defects had a 4.1-fold increased risk for a severe phenotype (95% CI: 1.18-14.42, P = 0.026) compared with other mutations. Of the polymorphisms studied, the FVII353Q (RR = 3.5, 95% CI: 1.04-12.05, P = 0.044) allele was associated with a severe phenotype. This data shows that apart from the F8/F9 genotype, functional polymorphisms in FVII gene affect the phenotype of patients with severe haemophilia.

Analysis of beta globin mutations in the Indian population: presence of rare and novel mutations and region-wise heterogeneity.

Beta thalassaemia is a major public health problem in India. A comprehensive database of the spectrum of mutations causing beta thalassaemia in the Indian population is necessary. This study in which a large number of patients with beta thalassaemia including those from certain regions that were not explored earlier shows a great heterogeneity of mutations. Several novel and rare alleles that have not been reported earlier in the Indian population have been identified, and mutations differ in frequency in different regions of the country. This information on the spectrum of mutations has implications for the control of beta thalassaemia in a population with complex ethnic background and also on the genotype-phenotype correlation of the disease.

Genotype phenotype correlation in Wilson's disease within families--a report on four south Indian families.

AIM: To study the genotype phenotype correlation in Wilson's disease (WD) patients within families. METHODS: We report four unrelated families from South India with nine members affected with WD. Phenotype was classified as per international consensus phenotypic classification of WD. DNA was extracted from peripheral blood and 21 exons of ATP7B gene and flanking introns were amplified by polymerase chain reaction (PCR). The PCR products were screened for mutations and the aberrant products noted on screening were sequenced. RESULTS: Four separate ATP7B mutations were found in the four families. ATP7B mutations were identical amongst affected members within each family. Three families had homozygous mutations of ATP7B gene while one family had compound heterozygous mutation, of which only one mutation was identified. We noted concordance between ATP7B gene mutation and Wilson's disease phenotype amongst members within each family. The age of onset of symptoms or of detection of asymptomatic disease, baseline serum ceruloplasmin and baseline urinary copper levels were also similar in affected members of each family. Minor differences in phenotype and baseline serum ceruloplasmin level were noted in one family. CONCLUSION: We report concordance between ATP7B mutation and WD phenotype within each family with > 1 member affected with WD. Homozygous ATP7B mutation was present in 3 of the 4 families studied. Our report supports allelic dominance as a determinant of WD phenotype. However, in one family with compound heterozygous mutation, there was a similar WD phenotype which suggests that there may be other factors determining the phenotype.

An anti-oxidant, α-lipoic acid conjugated oleoyl-sn-phosphatidylcholineas a helper lipid in cationic liposomal formulations.

Development of safe non-viral carrier systems for efficient intra-cellular delivery of drugs and genes hold promise in the area of translational research. Liposome based delivery systems have emerged as one of the attractive strategies for efficient delivery of drugs and nucleic acids. To this end, number of investigations was carried on liposomal formulations using lipids for achieving higher efficiency in transfection with lower cytotoxicities. In our efforts to develop safer and efficient liposomal delivery systems, we synthesized a novel anti-oxidant lipid, α-lipoyl, oleyl-sn-phosphatidylcholine (LOPC) and used as a helper lipid in combination with a cationic amphiphile, Di-Stearyl Dihydroxy Ethyl Ammonium Chloride (DSDEAC) and 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) at varying concentrations of LOPC. DNA binding properties of the liposomal formulations (DS, DS LA1, DS LA2 and DS LA3) revealed that increasing the percentage of single aliphatic chain lipid LOPC, did not affect the DNA binding properties. But, transfection profiles of these liposomal formulations in 3 different cell lines (HeLa, HEK 293 and MCF7) showed difference in their efficacies. Results showed that optimal percentage of LOPC i.e. 25% in DSDEAC and DOPC at 1:1 molar ratio (DS LA1) enhanced transfection as compared to DSDEAC:DOPC alone. The endosomal escape studies with NBD labelled lysotracker and Rhodamine labelled liposomal formulations revealed that DS LA1 and DS LA2 facilitated the release of genetic cargo with a better efficiency than their counter parts. Reactive Oxygen Species (ROS), a key modulator of necroptosis were lowered with the treatment of DS LA1 than other liposomal formulations. Here in, we present a novel liposomal formulation using DSDEAC and DOPC at 1:1 molar ratio doped with 25-50% (mole ratio) LOPC as an efficient delivery system for enhanced transfection with quenching of ROS levels compared to formulations without LOPC.

Developing an algorithm of informative markers for evaluation of chimerism after allogeneic bone marrow transplantation.

Analysis of chimerism by polymerase chain reaction amplification of STR or VNTR has become a routine procedure for the evaluation of engraftment after allogeneic stem cell transplantation. Knowledge of the frequency of different STR or VNTR alleles in unrelated individuals in a population is useful for forensic work. In the context of HLA identical sibling bone marrow transplantation the informativeness of these markers needs to be evaluated. We evaluated five STRs (THO1, VWA, FES, ACTBP2, and F13A1) and 1 VNTR (APOB) for informativeness in stem cell transplants from HLA identical sibling donors. All four markers used individually allowed us to discriminate 20-56% of the patient donor pairs. Using a combination of all these markers along with a polymorphic marker in the beta-globin gene and the sex chromosome specific amelogenin marker, we were able to discriminate 99% of the patient donor pairs. We have established an algorithm for evaluating chimerism following HLA identical sibling donor transplants in the Indian population using molecular markers in 310 patients. Analysis of heterozygote frequencies in different populations is similar suggesting that this algorithm can be used universally for transplant centers to evaluate chimerism following allogeneic bone marrow transplantation.

ATP7B mutations in families in a predominantly Southern Indian cohort of Wilson's disease patients.

OBJECTIVE: To analyze ATP7B mutations in Wilson's disease (WD) patients from the Indian subcontinent and to correlate these with WD phenotype. METHODS: We studied 27 WD patients from 25 unrelated families. Twenty-two families were from three southern Indian states - Tamil Nadu andhra Pradesh and Kerala. We applied conformation- sensitive gel electrophoresis (CSGE) to screen for the mutations in patients and their families. PCR products exhibiting aberrant patterns in CSGE were subjected to direct DNA sequencing. As siblings affected by WD within a family share identical ATP7B genotype, we compared WD phenotype among affected siblings within families. RESULTS: ATP7B mutations were detected in 22 of the 25 probands -13 were homozygotes and 9 were compound heterozygotes. Eleven novel mutations were detected. Only two common mutations were found: G3182A in 4 (16%) and C813A in 3 (12%) probands. 'Hot spots' for ATP7B mutations were exons 18 and 13. Lack of common dominant mutations prevented correlation of individual ATP7B mutations with WD phenotype. Symptomatic WD in a live sibling was not found in any family. In 8 families, a sibling died of presumed WD - in 6 of these, WD phenotype was identical to that in the proband. CONCLUSIONS: We describe the spectrum of ATP7B mutations including 11 novel mutations in Indian WD patients and document lack of a single dominant mutation. Identical WD phenotype among siblings in only 6 of 8 families with >1 child affected by WD suggests that factors other than ATP7B mutations influence WD phenotype.

Leukocyte Adhesion Deficiency-I: Clinical and Molecular Characterization in an Indian Population.

OBJECTIVE: To describe clinical and flow cytometric immunophenotyping details of 26 patients of Leukocyte adhesion deficiency-I (LAD-I) along with molecular characterization of 7 patients. METHODS: Diagnosis of LAD-I was suspected on the basis of clinical features, white blood cell count and absolute neutrophil counts and flow cytometric assessment of expression of CD18 and CD11(a, b, c) on leukocytes. Mutation analysis was performed using DNA PCR and conformation sensitive gel electrophoresis (CSGE) technique followed by sequencing. RESULTS: All the patients were symptomatic by the age of 6 mo, with history of recurrent bacterial infections involving skin, mucosa or umbilical cord (omphalitis) being the most frequent presenting symptoms. White blood cells (WBC) and absolute neutrophil counts (ANC) were markedly elevated, without any specific morphological findings. On flow cytometry, CD11a and CD11c showed moderate correlation with CD18 expression. Mutation analysis was performed in 7 patients and six different mutations (4 missense, 2 nonsense and 1 splice site) were identified, all of which were homozygous in nature. CONCLUSIONS: A presentation of repeated bacterial infections during infancy, especially omphalitis, with markedly elevated absolute neutrophil counts should trigger investigations for LAD-I including flow cytometric analysis of CD11/CD18 expression.

Molecular genetics of hereditary prothrombin deficiency in Indian patients: identification of a novel Ala362 --> Thr (Prothrombin Vellore 1) mutation.

Prothrombin deficiency is a rare (1:200 000) autosomal recessive disorder caused by diverse mutations in prothrombin gene. We have studied the molecular basis of this disorder in four unrelated Indian patients. The diagnosis was based on prolonged prothrombin (PT) and activated partial thromboplastin times and low factor II coagulant activity (FII: C) measured using a PT based assay. FII: C levels ranged between 4.7% and 17.5%. Mutations were identified in all the four patients. Five different causative mutations including four (80%) missense and an in-frame deletion (20%) were identified. One of them was a novel, Ala362 --> Thr amino acid change affecting 'B' chain of -thrombin. This mutation was present in a compound heterozygous state with a previously reported Arg-1 --> Gln missense change affecting pro-peptide cleavage site. Ala362 --> Thr occurred at a codon, evolutionarily conserved in all the 24 different prothrombins or its related serine proteases studied. Molecular modeling of this mutation was found to cause a conformational change around the region involving a catalytic triad residue His363 and a cysteine residue at codon 364. The FII: C level in this patient was 17.5%. Three other previously reported mutations were also detected in the homozygous state: Arg271 --> Cys in Kringle-2 region, a Glu309 --> Lys in "A" chain of -thrombin and an in-frame deletion of 3 bp (AAG) leading to Del Lys301/302 in "A" chain of -thrombin. This is the first report of the molecular basis of prothrombin deficiency in Indian patients and we suggest the eponym 'Prothrombin Vellore 1' for Ala362 --> Thr mutation.

Six novel mutations including triple heterozygosity for Phe31Ser, 514delT and 516T-->G factor X gene mutations are responsible for congenital factor X deficiency in patients of Nepali and Indian origin.

Factor X (FX) deficiency is a rare (1 : 100000) autosomal recessive disorder caused by heterogeneous mutations in FX gene. We have studied the molecular basis this disease in six Indian and one Nepali patients. Diagnosis was confirmed by measuring the FX coagulant activity (FX: C) using a PT based assay. Six of them had a FX: C of < 1% and one patient had 24% coagulant activity. Mutations were identified in all the seven patients. These included eight (88.8%) missense and one frame-shift (11.2%) mutations of which six were novel. Three of the novel mutations, a Phe31Ser affecting 'Gla' domain and 514delT and 516T-->G mutations affecting Cys132 in 'connecting region' were identified in a triple compound heterozygous state in a Nepali patient presenting with a severe phenotype. Two other novel mutations, Gly133Arg, may affect the disulphide bridge between Cys132-Cys302 in the connecting region while Gly223Arg may perturb the catalytic triad (His236, Asp282 and Ser379). The other novel mutation, Ser354Arg, involves the replacement of a small-buried residue by a large basic aminoacid and is likely to have steric or electrostatic effects in the pocket involving Lys351-Arg347-Lys414 that contributes to the core epitope of FXa for binding to FVa. Three previously reported mutations, Thr318Met; Gly323Ser; Gly366Ser were also identified. This is the first report of the molecular basis of FX deficiency in patients from the Indian subcontinent.

Fludarabine-based conditioning for allogeneic stem cell transplantation for multiply transfused patients with Fanconi's anemia.

A fludarabine-based protocol (fludarabine (25 mg/m(2)/day x 6 days), cyclophosphamide (10 mg/kg/day x 2 days) and ATG (ATGAM 10 mg/kg/day x 4 days)) was used in four multiply transfused Fanconi's anemia (FA) patients aged 5-15 years to reduce rejection during allogeneic bone marrow transplantation (BMT). Graft-versus-host disease (GVHD) prophylaxis consisted of cyclosporine and mini methotrexate. The graft source was G-CSF-stimulated bone marrow or peripheral blood stem cells (PBSC) in two patients each. All patients engrafted with median time to ANC>500/mm(3) being 14 days (range: 12-17) and unsupported platelet count >20 ,000/mm(3) being 13 days (range: 11-18). One patient had secondary graft rejection on day 56 and expired on day 69 due to fungal pneumonia. One patient who developed acute myeloid leukemia on day 56 underwent successful induction with cytosine and daunorubicin followed by peripheral blood stem cell (PBSC) rescue on day 70 and is presently in remission with complete donor chimerism and grade I GVHD. At a median follow-up of 13 months (range: 4-21), three patients (75%) are well with complete donor chimerism. Addition of fludarabine to the conditioning regimen for BMT in FA can provide additional immunosuppression for engraftment without increasing toxicity.

Treatment of children with newly diagnosed acute promyelocytic leukemia with arsenic trioxide: a single center experience.

A total of 11 children (five males and six females) with hypergranular type of acute promyelocytic leukemia (APML) were treated with intravenous arsenic trioxide (As(2)O(3)) between December 1998 and October 2003. Eight cycles of As(2)O(3) (0.15 mg/kg/day) were administered (induction, consolidation and six cycles of maintenance) over a period of 12 months. The median WBC count at diagnosis was 3400/mm(3) (range: 800-9800). In all, 10 patients (91%) achieved hematological remission at a mean duration of 48 days (range: 41-60) with all 10 patients achieving molecular remission at a median duration of 81 days (range: 64-109). Toxicity was minimal with leukocytosis in six patients, ichthyosis and hyperpigmentation of skin in five and mild peripheral neuropathy in one patient. One patient who relapsed 6 months after completing therapy achieved a second hematological and molecular remission with As(2)O(3). With a median follow-up of 30 months (range: 4-62), the overall (OS) survival is 91% with a relapse-free survival (RFS) of 81%. As(2)O(3) achieves hematological and molecular remission in majority of newly diagnosed children with APML with minimal toxicity, but long-term follow-up is required to evaluate late effects of As(2)O(3) and study the minimum dose and duration required for a sustained remission.

HCV genotype 4--an emerging threat as a cause of chronic liver disease in Indian (south) patients.

BACKGROUND: Hepatitis C virus (HCV) genotyping is relevant for the delivery of effective antiviral therapy. HCV genotypes are geographically restricted with genotype 4, which is resistant to therapy, traditionally considered to be confined to the Middle East and Africa. We report here on the occurrence of HCV genotype 4 in Indian (South) patients. OBJECTIVES: 1) To highlight the occurrence of HCV genotype 4 in the patient population attending a tertiary care hospital in south India. 2) To ascertain the difference in HCV viral loads and alanine aminotransferase (ALT) values between patients infected with HCV genotype 4 and those infected with the other two most commonly detected genotypes in this patient population viz., HCV genotypes 1 and 3. 3) To assess the genetic relatedness of the Indian strains to Genbank sequences, which we report for the first time. STUDY DESIGN: The study group consisted of 125 HCV infected, untreated patients who had been genotyped using type specific primers. Eight of the nine samples classified as HCV genotype 4 by this technique were subjected to nucleotide sequencing. Viral load estimations were carried out. Information on possible risk factors and ALT values were obtained from hospital records. Statistical analyses were carried out to compare viral loads and ALT values across genotypes. A phylogenetic tree was constructed and the genetic relatedness of the strains was assessed through sequence analysis. RESULTS: HCV genotype 4 was detected in nine of 125 (7.2%) patients. Eight of the nine were subjected to nucleotide sequencing and all strains were confirmed as HCV genotype 4. Six of the eight strains were closely related, with two strains being phylogenetically diverse. CONCLUSIONS: HCV genotype 4 is detected in a significant minority of HCV infected patients in India. This finding should be considered in designing strategies prior to initiation of therapy in Indian patients infected with HCV.

Distribution of the different genotypes of HCV among patients attending a tertiary care hospital in south India.

BACKGROUND: Genotyping of the hepatitis C virus (HCV) and assessment of viral load is important for designing therapeutic strategies and region specific diagnostic assays. OBJECTIVES: To determine the distribution of HCV genotypes among patients attending a tertiary care hospital in south India, and to correlate this with viral load. STUDY DESIGN: Ninety HCV RNA positive patients were recruited for the study. HCV genotyping was carried out using type-specific primers from the core region of the viral genome [J. Clin. Microbiol. 35 (1997) 201]. Viral load estimations were carried out using the Amplicor HCV Monitor (Versions 1.5 and 2, Roche Diagnostics, Branchburg, NJ, USA). Clinical details were elicited from patients' hospital records. RESULTS: Genotype 3 was detected most frequently (62.2%) followed by infection with HCV genotype 1 (18.8%). There was no significant difference seen in alanine aminotransferase (ALT) values between the two genotypes. Genotype 1 was associated with a significantly higher viral load as compared with genotype 3 (P=0.001). Parenteral transmission accounted for 61% of all infection caused. Infection with genotype 1 was significantly associated with a history of haemodialysis (P=0.01). Genotype 3 was detected more frequently in patients from east India, as compared with its detection in patients from south India (P=0.004). Similarly, genotype 1 was detected with greater frequency in individuals from south India as compared with patients from east India (P=0.004). The concordance between Ohno's genotyping assay and nucleotide sequencing, for genotypes 1 and 3, was 75%. CONCLUSIONS: HCV genotypes 1 and 3 accounted for 81% of HCV infections in patients from this geographical region. HCV genotype distribution showed regional differences and genotype 1 was associated with higher viral loads. Parenteral transmission was the major route for acquisition of HCV infection. Ohno's type-specific primer based genotyping assay can be used for distinguishing between HCV genotype 1 and non-1 HCV genotypes in laboratories that do not possess nucleotide sequencing facilities.

HPV DNA in plasma of patients with cervical carcinoma.

BACKGROUND: HPV DNA has been detected in metastatic tumour and HPV plasma viraemia may indicate a poor prognosis and a high risk for metastasis. OBJECTIVE: Detection of HPV DNA in plasma of patients with cervical carcinoma. STUDY DESIGN: A cross-sectional study was done, wherein cervical biopsies and plasma samples were collected from 58 women with invasive cervical carcinoma, 10 women with cervical intraepithelial neoplasia (CIN) and 30 control women in the same age range. Polymerase chain reaction (PCR) was employed to detect the presence of HPV DNA. Samples positive for HPV DNA were typed by restriction fragment length polymorphism (RFLP). To confirm that the HPV sequence in plasma was identical to that in tissue, sequencing was done on all the paired plasma and tissue samples. RESULTS: All the 30 paired cervical tissue and plasma samples from the controls were negative for HPV DNA. HPV DNA was detectable in cervical tissues of 55 (94.8%) of 58 patients with invasive cervical carcinoma and in all 10 patients (100%) with CIN and in eight (11.8%) of the total 68 plasma samples from patients. All eight plasma samples were from women with invasive cervical carcinoma with three each in stages IIIB and IV and one each in stages IIB and IB, respectively. Of the eight positive samples, seven were typed as HPV-16 and 1 as HPV-58. HPV types detected in cervical tissue and plasma pairs from these eight patients correlated as revealed by RFLP and sequencing. A patient with stage IB cancer had detectable HPV DNA in the external iliac lymph node, removed at Wertheims hysterectomy, which was histopathologically free of tumour. The HPV type in the node, was the same as that present in the paired tissue and plasma sample. CONCLUSIONS: HPV DNA is detectable in the plasma of patients with advanced cervical cancer.

Molecular remission with arsenic trioxide in patients with newly diagnosed acute promyelocytic leukemia.

Thirty six APML patients achieving hematological remission with As2O3 were serially monitored using RT-PCR. Though only 5.5% achieved molecular remission at induction remission, 94.5% became negative during consolidation. At 20 months follow-up, 85% remain in remission but longer follow up studies are needed to monitor late relapses.

Prenatal diagnosis of beta-thalassaemia mutations using the reverse dot blot technique.

BACKGROUND: Beta-thalassaemia is the most common genetic disorder among Indians and a number of mutations causing this disease have been reported. Since effective treatment of thalassaemia major is complicated and very expensive, prenatal diagnosis has become an important option for those at risk of having an affected foetus. We report the use of a rapid hybridization method called 'reverse dot blot' for detection of specific mutations of the beta-globin gene. METHODS: DNA was obtained from a 12-week-old foetus by chorionic villus sampling and was amplified using specific primers by the polymerase chain reaction and analysed by the reverse dot blot test. Results were available within 36 hours after sampling. RESULT: The father and mother were found to be heterozygous for codon 15 (G-A) mutation of the beta-globin gene. The foetus was normal. CONCLUSION: Reverse dot blot is a rapid and reliable technique for mutation detection in the beta-globin gene and can be useful for antenatal diagnosis.

An outbreak of echovirus meningitis in children.

An outbreak of aseptic meningitis in children as evidenced by increase in the number of admissions in a tertiary care hospital is described. Clinical data and stool samples were collected from 25 hospitalized infants and young children. The stool samples were subjected to virological investigations. Fever and vomiting were the commonest symptoms. Cerebrospinal fluid (CSF) showed lymphocytic pleocytosis in majority of cases. Of the 25 stool samples, 14 showed an enterovirus specific cytopathogenic effect (CPE) in rhabdomyosarcoma (RD) cell line. All the 14 samples were positive for enterovirus RNA by reverse transcription-polymerase chain reaction (RT-PCR). Partial sequencing of the Virion protein 1 (VPI) region of the enterovirus genome carried out on the first 7 isolates revealed 5 isolates to be echovirus serotype 4 and one each to be echovirus serotypes 3 and 30. All children showed a rapid recovery and were discharged within 3 days of admission.

A novel δ-globin gene mutation (HBD: c.323G>A) masking the diagnosis of ß-thalassemia: a first report from India.

An elevated HbA(2) (α2δ2) level (>3.5%) is a well-established diagnostic test for heterozygous ß-thalassemia. Mutations in the δ-globin gene can cause decreased expression of HbA(2), resulting in heterozygous ß-thalassemia with normal levels of HbA(2). In this report, we describe a novel missense mutation in δ-globin (HBD: c.323G>A, Gly > Asp) in an Indian family with heterozygous ß-thalassemia with normal HbA(2) levels.

A novel ß-globin gene mutation HBB.c.22 G>C produces a hemoglobin variant (Hb Vellore) mimicking HbS in HPLC.

Hemoglobinopathies are highly prevalent in Indian population. DNA analysis to detect causative mutations is required for identifying rare hemoglobin variants or when hematological results are discordant with the clinical phenotype. In this report, we describe a novel hemoglobin variant caused by a mutation in beta-globin gene, Codon 7 GAG→CAG (Glu→Gln) that elutes in the position of sickle haemoglobin (HbS) in cation exchange high performance liquid chromatography. This report highlights possible diagnostic pitfalls in interpreting data solely based on haemoglobin analysis and usefulness of mutation screening in definitive diagnosis of hemoglobinopathies.