Influence of tissue factor polymorphisms (603A>G and 5466A>G) on plasma tissue factor levels and their impact on deep vein thrombosis risk in young Indian population.

Deep vein thrombosis (DVT) is multifactorial disorder and well known to cause substantial morbidity and mortality. There is sparse data in the Asian population, particularly India regarding association of tissue factor (TF) gene single nucleotide polymorphisms (SNPs) with plasma TF levels in DVT. So, we analyzed the distribution of SNPs (603A>G and 5466A>G) in India, to evaluate their effect on TF levels in DVT patients. Plasma level and SNPs (603A>G and 5466A>G) of TF gene were screened in subjects (100 DVT patients and 100 controls). Patients had significantly higher TF levels than controls (patients: 84.95 ± 17.16 pg/ml, controls: 70.55 ± 15.87 pg/ml, p < 0.001). G allele of 603A>G polymorphism was significantly higher in patients than controls (patients: 40.5% controls: 27.5%, p = 0.004). Subjects with AG and GG genotype had significantly higher TF levels than AA genotype (p = 0.001). After multiple logistic regression analysis, risk of DVT was increased 1.398 fold (95% CI 0.738-2.651) and 4.41 fold (95% CI 1.404-13.884) with AG and GG genotype respectively. Allelic and genotypic frequencies of 5466A>G polymorphism was neither associated with TF levels nor with DVT. We found high TF level in patients with TF 603A>G polymorphism, which is an important predisposing factor in increasing risk of DVT in young Indians. Furthermore, GG genotype of 603A>G polymorphism augments the risk of thrombosis by 4.4 fold, thus highlighting the significance of this polymorphism in the development of DVT. So, we suggest that inclusion of 603A>G polymorphism in prothrombotic work-up may be helpful in making the treatment strategy in DVT patients.

Evaluation of role of FV, FVIII and APLAs in the pathogenesis of APCR in FV Leiden negative DVT patients: a study in India.

Resistance to APC (APCR) is a very important cause of thrombophilia and most frequently caused by the Leiden mutation. APCR is also seen in the absence of FV Leiden and associated with elevated levels of factor V (FV), factor VIII (FVIII) and antiphospholipid antibodies (APLAs). The aim of this prospective case control study was to find out the frequency and role of FV, FVIII and APLAs in the pathogenesis of APCR in FV Leiden negative deep vein thrombosis (DVT) patients in India. A total 30 APCR positive and FV Leiden negative patients with DVT and similar number of age and sex matched healthy controls were recruited. Significantly higher mean FVIII levels were observed in patients as compared to controls [patients: 132.3 ± 30.7 IU/ml, controls: 117.5 ± 17.7 IU/ml, p = 0.025]. A significant negative correlation was also observed between FVIII and APC ratio (Pearson correlation = 0.368, p = <0.001). Mean FV levels in patients [107.1 ± 13.1 IU/ml] and controls [102 ± 11.9 IU/ml] were not statistically significant (p = 0.119). Anti ß2 glycoprotein I (Anti-ß2-GPI, IgG) showed significant association with APCR phenotype (p = 0.050), unlike other factors such as protein C, protein S, lupus anticoagulant and anticardiolipin antibodies. The strong association of FVIII and anti-ß2 GPI (IgG) antibodies with APCR phenotype is suggestive of incorporation of these factors in APCR positive DVT patients in the absence of FV Leiden mutation in India. However more studies in large sample size are required for setting up the proper investigation protocol in these patients.

Prevalence and Impact of HMOX1 Polymorphism (rs2071746: A > T) in Indian Sickle Cell Disease Patients.

Introduction Fetal hemoglobin (HbF) levels play significant role in lowering down the morbidity and mortality in sickle cell disease (SCD) patients. Coinheritance of heme oxygenase-1 (HMOX1) rs2071746:A > T polymorphism may contribute to variable HbF levels in Indian SCD patients. Objective This study was aimed to evaluate the role of HMOX1 polymorphism and its impact on HbF level in Indian SCD patients. Materials and Methods One-hundred twenty confirmed cases of SCD and 50 healthy controls were recruited. Their mean age was 11.5 ± 8.6 years (range: 3-23 years). Quantification of Hb, HbA2, HbF, and HbS was done by capillary zone electrophoresis. Allele-specific polymerase chain reaction was used to genotype HMOX1 (rs2071746:A > T) gene polymorphism. Results Out of the 120 cases of SCD, 65 were hemoglobin sickle-shaped (HbSS) and 55 were sickle-beta thalassemia (Sß). Out of 65 HbSS patients, 29 (44.6%) were heterozygous (AT), 20 (30.76%) were homozygous (TT), and 16 (24.61%) were found wild-type (AA) genotype. Out of 55 Sß, 22 (40%) were heterozygous, 18 (32%) were homozygous and 15 (28%) were wild-type. Patients carrying HMOX1 (rs2071746:A > T), AT, and TT genotypes had less anemia, painful crisis, splenomegaly, hepatomegaly, jaundice, and blood transfusion. HbF level was found higher in TT genotype (in HbSS the HbF levels was 25.1 ± 4.4; in sickle-beta thalassemia the HbF levels was 36.1 ± 4.7) than wild-type(AA) and was statistically significant ( p -value <0.001). Conclusion The TT genotype of the rs2071746:A > T polymorphism was associated with increased levels of Hb F ( p < 0.001). It can serve as a HbF modifier in Indian sickle cell diseases patients.

Clinical variability and molecular characterization of Hbs/Gγ (Aγδß)0-thal and Hbs/HPFH in Indian sickle cell disease patients: AIIMS experience.

INTRODUCTION: In sickle cell disease (SCD) patients, among the predictors of survival, HbF levels play a significant role in lowering the morbidity and mortality. Coinheritance of 뫧 thalassemia and hereditary persistence of fetal hemoglobin (HPFH) may contribute to variable HbF levels in SCD patients, thus influencing their clinicopathological profile. Such cases are sparsely documented in the literature and thus, we screened the presence of 뫧 thalassemia and HPFH in 126 cases of SCD with high HbF. MATERIAL AND METHODS: A total 126 SCD individuals with raised HbF levels were the study subject. Capillary zone electrophoresis (CZE) was done for the quantitative assessment of hemoglobin variants. HbSC, HbSD, HbAS and HbSE cases were excluded. Asian Indian Gγ(Aγδß)0-thal, δß0-thal (Sicilian, 13.4 kb), (Chinese, 100 kb), HPFH-1 (Black, 106 kb), HPFH-2 (Ghanaian, 105 kb), HPFH-3 (Indian, 48.5 kb) were done by GAP-PCR. RESULTS: Out of 126, 78 cases (62%) were homozygous for SCD. The remaining 48 cases suspected to be heterozygous were furthered screened and 6/48 cases (12.5%) were found to be compound heterozygous. Out of these 6 cases,4(66.66%) had HbS/ δß- Gγ(Aγδß)0 and 2(33%) had HbS/HPFH compound heterozygous condition. None of the patients had δß0-thal (Sicilian, 13.4 kb), (Chinese, 100 kb), HPFH-1 (Black, 106 kb), HPFH-2 (Ghanaian, 105 kb). CONCLUSION: This study highlights the importance of understanding the complex patho-physiology of compound heterozygous cases of HbS/HPFH and HbS/뫧 thalassemia, as these infrequent conditions lead to change in phenotype and clinical severity of the disease. Insight into more such cases will open the window to better analyze the disease pathogenesis in these rare compound heterozygous conditions, as this will be beneficial to formulate proper management protocol in these patients.

Contrasting co-inheritance of alpha and beta mutations in delta beta thalassemia and hereditary persistence of fetal hemoglobin: a study from India.

BACKGROUND AND OBJECTIVES: Coinheritance of 뫧 thalassemia and HPFH with inherited factors is sparsely documented and may affect treatment modalities. So, we screened the presence of α deletion and ß mutations in 뫧 thalassemia and HPFH disorders in 52 cases with high Hb F concentration. MATERIAL AND METHODS: Fifty-two individuals with raised HbF levels were study subjects. CZE was done for quantitative assessment of hemoglobin variants. Asian Indian inversion deletion break point type A, B and HPFH-3 were done by GAP-PCR. RESULTS: 18/52 cases of 뫧 Gγ (Aγδß)0 thalassemia and 28/52 cases of HPFH-3 deletion were characterized. 6/52 patients with raised HbF levels were negative for 뫧 Gγ (Aγδß)0 and HPFH-3 deletion. 9/18 (50%) were heterozygous for Gγ(Aγδß)0 break point type A, 6/18 (33%) were heterozygous for break point type B and 3/18 (17%) were homozygous. Of the nine patients heterozygous for Gγ(Aγδß)0 break point type A, three (33%) patients were double heterozygous with alpha 3.7 kb deletion and two (22%) patients showed compound heterozygosity with IVS 1-5(G-C) mutation. 4/9 (45%) patients were Gγ(Aγδß)0 heterozygous. DISCUSSION AND CONCLUSION: We found 5/18(27.ß) δß-thalassemia cases with co-inherited alpha 3.7 deletion and 3/18 (16ß) cases with IVS 1-5(G-C) mutation. Patients showed features of thalassemia intermedia phenotype among which those with co-inherited IVS 1-5(G-C) mutation showed severe phenotype as compared to those with co-inherited alpha 3.7 deletion. So, we highlight importance of genotyping of patients with 뫧 thalassemia or HPFH and coinheritance with inherited factors which plays crucial role in clinicopathological profile and setting up prenatal diagnostic protocol.

Impact of interleukin 6 promoter polymorphisms (-174 G > C, -572 G > C and -597 G > A) on plasma IL-6 levels and their influence on the development of DVT: a study from India.

OBJECTIVES: To evaluate the association of interleukin 6 (IL-6) levels with deep vein thrombosis (DVT) and to assess the impact of IL-6 promoter polymorphisms (-174G > C, -572G > C and -597G > A) on its plasma levels and their influence in the development of DVT in India. METHODS: One hundred DVT patients and 100 age and sex-matched healthy controls were study subjects. IL-6 polymorphisms were identified by polymerase chain reaction-restriction fragment length polymorphism. IL-6 levels were detected by enzyme-linked immunosorbent assay. RESULTS: Significantly raised IL-6 levels were observed in patients as compared to controls. (Patients: 13.73 ± 6.30 pg/ml, Controls: 11.83 ± 4.47 pg/ml, p = 0.014). The prevalence of C allele of -572G > C polymorphism was significantly higher in patients than controls (Patients: 39.5%, Controls: 27.5%, p = 0.011, χ2=6.463). Subjects with GC and CC genotype had significantly higher IL-6 levels than GG genotype (p=<0.001). Patients with GC and CC genotype increased the DVT risk by 1.39 fold (ORa: 1.39, CI: 0.74-2.62) and 2.69 fold (ORa: 2.42, CI: 1.08-6.70), respectively. IL-6 -174G > C and -597G > A polymorphisms were not associated with raised IL-6 levels and nor with thrombotic risk (-174G > C: p = 0.823 χ2=0.369; -597G > A: p = 0.678 χ2=1.08). CONCLUSION: Our study emphasizes the importance of -572G > C polymorphism in increasing IL-6 levels, thereby showing its significant role in DVT in India. IL-6 -174G > C and -597G > A were neither associated with raised plasma IL-6 levels nor with thrombotic risk. Thus -572G > C polymorphism detection may be one of the connecting links between IL-6 and thrombotic risk in Indian DVT patients.