Unbalanced globin chain synthesis in reticulocytes of sickle cell trait individuals with low concentrations of hemoglobin S (original) (raw)
Related papers
American Journal of Hematology, 1991
In 113 black American adults with sickle cell anemia (HbSS), we examined nine polymorphic restriction sites, including the Xmnl site 5' to the Gy gene, to see whether haplotype is related to the level of HbF and the proportion of G-y chains or if it influences the hematological and clinical features of the disease. Seventy-five percent of the patients were homozygous or heterozygous for the Benin (no. 19) or Central African Republic (Bantu, no.20) haplotypes; 13.3% were hornozygous or heterozygous for the Senegal (no. 3) haplotype, while 11.5% had other genotypes. Of the subjects, 14.2% were either homozygous or heterozygous for the Xmnl restriction site 5' to the Gy gene. We found no effect of haplotype on HbF levels. The level of Gy chains was 60.5% ? 17.0% in individuals heterozygous or homozygous for haplotype no. 3 and was 46.9% * 11.6% in individuals with other haplotypes. Subjects with the Xmnl site 5' to the Gy gene had Gy globin levels of 59.5% _f 16.7% while those lacking that site had an average of 47.2% ? 12.1%. There were no significant differences among these groups in hemoglobin concentration, packed cell volume, mean cell volume, or clinical indicators of vaso-occlusive severity, including crises, hospitalizations per year, aseptic bone necrosis, acute chest syndrome, or leg ulcers. While the presence of haplotype 3 and the 5' Gy Xmnl site were associated with increased Gy chains, there was no effect on HbF level or other hematological and clinical features that might reflect disease severity. It is likely that determinants unrelated to haplotype, linked or unlinked to the p-globin gene cluster, are the major effectors of differences in the levels of HbF in American patients with sickle cell anemia.
Hemoglobin Patterns in Patients with Sickle Cell Hemoglobinopathies
2016
Background: Hemoglobinopathy is a group of inherited disorders characterized by structural variations of the hemoglobin molecule; and sickle cell disease constitutes one of the major genetic blood disorders in Sudan. The aim of this study was to determine the hemoglobin patterns of patients with sickle cell hemoglobinopathies. Methods: This is a hospital based case control study conducted at the Military Hospital, Omdurman. A total of 100 blood samples were collected, 70 cases diagnosed or suspected to have sickle cell disease and 30 was healthy control. Sickling test and hemoglobin (Hb) electrophoresis were performed using Capillary 2 Flex Piercing (SEBIA). Results: Capillary Hb electrophoresis exposed the following variants of sickling hemoglobinopathies among cases group: 37 patients (52.9%) AS pattern, 1 patient (1.4%) AS/C Pattern, 8 patients (11.4%), S/B Thalassemia pattern, 1 patient (1.4%) S/C pattern, 3 patients (4.3%) S/D pattern and 20 patients (28.6%) SS pattern. While H...
2014
Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, King Saud University, Riyadh 11451, Saudi Arabia E-mail : manalkhalid2005@yahoo.com, sarjumand13@gmail.com, muskaanht@yahoo.com, sfatima2013@yahoo.com, noura_jameil@yahoo.com Manuscript received online 29 October 2013, revised 08 November 2013, accepted 09 January 2014 Approximately 5% of the world's population carries trait genes for haemoglobin disorders, mainly, sickle cell disease and thalassemia. Haemoglobin disorders are genetic blood diseases due to inheritance of mutant haemoglobin genes from both, generally healthy parents. Sickle cell disease and <strong>β</strong>-thalassaemia are most common in eastern province of Saudi Arabia. The present study was undertaken to analyze the variation in levels of haemoglobin (<strong>Hb</strong>) types in different haemoglobin disorders in samples of patients from Riyadh, Saudi Arabia by <strong>CAE</strong> and <s...
Changes in Globin Synthesis With Erythroid Cell Maturation in Sickle Thalassemia
Blood, 1973
Biochemical studies of different groups of patients with sickle β-thalassemia (S-thal) are described. In a group of relatively asymptomatic black patients with sickle thalassemia, there is mild anemia and no clinical symptomatology. α and β-type (βA,βS, and γ) globin chain synthesis in these patients is balanced in bone marrow cells, although there is an excess of α-over β-type chain synthesis in peripheral blood. These mildly affected patients are in contrast to two other groups of S-thal patients of both Mediterranean and black extraction who have anemia and clinical symptomatology and in whom there is absent or more decreased βA-chain production.
Haptoglobin Genotypes in Sickle-Cell Disease
Genetic Testing and Molecular Biomarkers, 2011
We compared the frequencies of the haptoglobin (Hp) genotypes of 775 Brazilian patients with sickle-cell disease divided into the following age groups: 3 months-5 years, 6-10 years, 11-15 years, 16-20 years, and over 20 years. The last group (> 20 years) was also compared with a healthy control group and was further divided into subgroups including only subjects aged 21-30 years (V.a and Control.a) and over 30 years (V.b and Control.b). There was no significant difference in the frequencies of the Hp genotypes between the different patient groups or between the patients and controls. However, the Hp2-2 genotype was always less frequent than the Hp1-1 genotype in the patient groups, whereas the opposite was observed in healthy controls. The frequency of Hp2-2 was 25.0% in patients in the 21-30 years age group and fell to 19.5% in those over 30 years. In the controls, the corresponding frequency was around 28%. Although our results do not allow us to conclude that Hp genotypes on their own confer greater or lesser selective advantage on sickle-cell disease patients in the population studied, this polymorphism may, when combined with other genetic and environmental factors, contribute to the clinical diversity observed in this disease.