Ancestry of the major long-range regulatory site of the α-globin genes in the Portuguese population with the common 3.7 kb α-thalassemia deletion.

Background: The α-Major Regulatory Element (α-MRE), also known as HS-40, is located upstream of the α-globin gene cluster and has a crucial role in the long-range regulation of the α-globin gene expression. This enhancer is polymorphic and several haplotypes were identified in different populations, with haplotype D almost exclusively found in African populations. The purpose of this research was to identify the HS-40 haplotype associated with the 3.

Differential expression of adhesion molecules in sickle cell anemia and gut microbiome effect.

Sickle cell anemia (SCA) causes a long-standing vascular inflammation state, leading to endothelial dysfunction and chronic overexpression of several adhesion molecules, which contributes to acute and constant vaso-occlusive (VOC) episodes. It has been demonstrated that hydroxyurea (HU) can reduce VOC events, organ damage, blood transfusions, and even the adhesion properties to endothelial cells of SCA subjects. Due to VOC episodes, these patients are also more susceptible to recurrent bacterial translocation and dysbiosis.

Are Genetic Modifiers the Answer to Different Responses to Hydroxyurea Treatment?-A Pharmacogenetic Study in Sickle Cell Anemia Angolan Children.

Sickle cell anemia (SCA) is an inherited disease affecting the hemoglobin that is particularly common in sub-Saharan Africa. Although monogenic, phenotypes are markedly heterogeneous in terms of severity and life span. Hydroxyurea is still the most common treatment for these patients, and the response to treatment is highly variable and seems to be an inherited trait.

Microbial gut evaluation in an angolan paediatric population with sickle cell disease.

Sickle cell disease (SCD) is one of the most common genetic conditions worldwide. It can contribute up to 90% of under-5 mortality in sub-Saharan Africa. Clinical manifestations are very heterogeneous, and the intestinal microbiome appears to be crucial in the modulation of inflammation, cell adhesion and induction of aged neutrophils, the main interveners of recurrent vaso-occlusive crisis.

How Hydroxyurea Alters the Gut Microbiome: A Longitudinal Study Involving Angolan Children with Sickle Cell Anemia.

Sickle cell anemia (SCA) is an inherited hematological disorder and a serious global health problem, especially in Sub-Saharan Africa. Although hydroxyurea (HU) is the leading treatment for patients with SCA, its effects on the gut microbiome have not yet been explored. In this context, the aim of this study was to investigate this association by characterizing the gut microbiome of an Angolan SCA pediatric population before and after 6 months of HU treatment.

Genotypic Diversity among Angolan Children with Sickle Cell Anemia.

Background: Sickle cell anemia (SCA) is an inherited blood disorder that affects over 300,000 newborns worldwide every year, being particularly prevalent in Sub-Saharan Africa. Despite being a monogenic disease, SCA shows a remarkably high clinical heterogeneity. Several studies have already demonstrated the existence of some polymorphisms that can provide major clinical benefits, producing a mild phenotype.

Co-Inheritance of alpha-thalassemia and sickle cell disease in a cohort of Angolan pediatric patients.

The aim of this study was to explore the association between alpha-thalassemia, fetal hemoglobin, hematological indices, and clinical adverse events in Angolan sickle cell disease pediatric patients. A total of 200 sickle cell disease (SCD) children were sampled in Luanda and Caxito. A venous blood sample was collected and used for hematological analyses, fetal hemoglobin quantification, and genotyping of 3.

Widening the spectrum of deletions and molecular mechanisms underlying alpha-thalassemia.

Inherited deletions of α-globin genes and/or their upstream regulatory elements (MCSs) give rise to α-thalassemia, an autosomal recessive microcytic hypochromic anemia. In this study, multiplex ligation-dependent probe amplification performed with commercial and synthetic engineered probes, Gap-PCR, and DNA sequencing were used to characterize lesions in the sub-telomeric region of the short arm of chromosome 16, possibly explaining the α-thalassemia/HbH disease phenotype in ten patients. We have found six different deletions, in heterozygosity, ranging from approximately 3.

Mutational spectrum of delta-globin gene in the Portuguese population.

The phenotype of increased Hb A2 typical of beta-thalassaemia (beta-thal) carriers can be reduced to normal or borderline values because of the co-inheritance of a delta-globin gene (HBD, MIM #142000) mutation, which may lead to misinterpretation of diagnostic results. To know the spectrum of delta-globin mutations in the Portuguese population we performed a mutational analysis of the delta-globin gene in a group of 51 Portuguese beta-thal carriers presenting microcytosis, hypochromia and a normal/borderline Hb A2 level and in another group of 15 individuals suspected to have delta-globin structural abnormalities. The heterozygosity for the beta(+)IVS-I-6T-->C (HBB:c.

Hb Evora [alpha2-35 (B16), Ser-->Pro], a novel hemoglobin variant associated with an alpha-thalassemia phenotype.

We report a novel mutation in the alpha2-globin gene, codon 35 (T-->C), detected in two unrelated Portuguese families. This mutation gives rise to a previously undescribed hemoglobin (Hb) variant, which we named Hb Evora. This variant seems to be responsible for the alpha-thalassemia phenotype present in its carriers.

Hemoglobin Loves Park [beta68 (E12) Leu-->Phe]: report of five cases including one originating from a de novo mutation.

Hemoglobin (Hb) Loves Park [beta68 (E12) Leu-->Phe] was identified in a 2-year-old Portuguese boy with anemia, microcytosis, and hypochromia. This Hb variant was detected by isoelectric focusing and quantified by reverse-phase high-performance liquid chromatography (HPLC) (48.4%), and the DNA mutation was identified by HBB (beta-globin gene) sequencing.

The role of HFE mutations on iron metabolism in beta-thalassemia carriers.

Hereditary hemochromatosis (HH) is an autosomal recessive disorder of iron metabolism characterized by increased iron absorption and progressive storage resulting in organ damage. HFE gene mutations C282Y and H63D are responsible for the majority of HH cases. A third HFE mutation, S65C, has been associated with the development of a mild form of hemochromatosis.

Hb Yaoundé [beta134(H12)Val-->Ala] in association with Hb C [beta6(A3)Glu-->Lys] in a Caucasian Portuguese family.

Hb Yaoundé [beta134(H12)Val-->Ala] is a rare, silent and asymptomatic hemoglobin (Hb) variant. It was previously reported in a Black man from Cameroon, in association with Hb Kenitra [beta69(E13)Gly-->Arg], and was subsequently found and described as Hb Mataro in a sub-Saharan child. To date, Hb Yaoundé has not been described in Caucasian people and molecular studies have never been performed.

Asymptomatic homozygous deletional beta(0)-thalassemia in an African individual.

Homozygosity or compound heterozygosity for beta(0)-thalassemia mutations most commonly results in a transfusion-dependent thalassemia major phenotype. In this report, we describe a 55-year-old male, from Guinea-Bissau, that had been asymptomatic and never transfused until being admitted to hospital with anemia, fever, splenomegaly, and asthenia. Following hospital admission, HIV-2 and Mycobacterium tuberculosis infections were diagnosed, and biochemical and molecular studies revealed homozygosity for beta(0)-thalassemia.