title: Phenotypic Diversity of Sickle Cell Disease in Patients with a Double Heterozygosity for Hb S and Hb D-Punjab.
abstract: Phenotypic heterogeneity for sickle cell disease is associated to several genetic factors such as genotype for sickle cell disease, β-globin gene cluster haplotypes and Hb F levels. The coinheritance of Hb S (HBB: c.20A > T) and Hb D-Punjab (HBB: c.364G > C) results in a double heterozygosity, which constitutes one of the genotypic causes of sickle cell disease. This study aimed to assess the phenotypic diversity of sickle cell disease presented by carriers of the Hb S/Hb D-Punjab genotype and the Bantu [- + - - - -] haplotype. We evaluated medical records from 12 patients with sickle cell disease whose Hb S/Hb D-Punjab genotype and Bantu haplotype were confirmed by molecular analysis. Hb S and Hb D-Punjab levels were quantified by chromatographic analysis. Mean concentrations of Hb S and Hb D-Punjab were 44.8 ± 2.3% and 43.3 ± 1.8%, respectively. Painful crises were present in eight (66.7%) patients evaluated, representing the most common clinical event. Acute chest syndrome (ACS) was the second most prevalent manifestation, occurring in two individuals (16.7%). Three patients were asymptomatic, while another two exhibited greater diversity of severe clinical manifestations. Medical records here analyzed reported a significant clinical diversity in sickle cell disease ranging from the absence of symptoms to wide phenotypic variety. The sickle cell disease genotype, Bantu haplotype and hemoglobin (Hb) levels did not influence the clinical diversity. Thus, we concluded that the phenotypic variation in sickle cell disease was present within a specific genotype for disease regardless of the β-globin gene cluster haplotypes.
authors.affiliation: a Laboratory of Hemoglobin and Hematologic Genetic Diseases , São Paulo State University (UNESP) , São Paulo , Brazil.
authors.forename: Lidiane S
authors.initials: LS
authors.lastname: Torres
authors.affiliation: a Laboratory of Hemoglobin and Hematologic Genetic Diseases , São Paulo State University (UNESP) , São Paulo , Brazil.
authors.forename: Jéssika V
authors.initials: JV
authors.lastname: Okumura
authors.affiliation: a Laboratory of Hemoglobin and Hematologic Genetic Diseases , São Paulo State University (UNESP) , São Paulo , Brazil.
authors.forename: Édis
authors.initials: É
authors.lastname: Belini-Júnior
authors.affiliation: a Laboratory of Hemoglobin and Hematologic Genetic Diseases , São Paulo State University (UNESP) , São Paulo , Brazil.
authors.forename: Renan G
authors.initials: RG
authors.lastname: Oliveira
authors.affiliation: a Laboratory of Hemoglobin and Hematologic Genetic Diseases , São Paulo State University (UNESP) , São Paulo , Brazil.
authors.forename: Patrícia P
authors.initials: PP
authors.lastname: Nascimento
authors.affiliation: a Laboratory of Hemoglobin and Hematologic Genetic Diseases , São Paulo State University (UNESP) , São Paulo , Brazil.
authors.forename: Danilo G H
authors.initials: DG
authors.lastname: Silva
authors.affiliation: b Clinical Hematology Division , Institute of Hematology Arthur de Siqueira Cavalcanti (HEMORIO) , Rio de Janeiro , Brazil.
authors.forename: Clarisse L C
authors.initials: CL
authors.lastname: Lobo
authors.affiliation: c Laboratory of Immunomorphology , São Paulo State University (UNESP) , São Paulo , Brazil.
authors.forename: Sonia M
authors.initials: SM
authors.lastname: Oliani
authors.affiliation: a Laboratory of Hemoglobin and Hematologic Genetic Diseases , São Paulo State University (UNESP) , São Paulo , Brazil.
authors.forename: Claudia R
authors.initials: CR
authors.lastname: Bonini-Domingos
mesh_terms: D056586:Acute Chest Syndrome / Q000209:etiology; D000755:Anemia, Sickle Cell / Q000150:complications / Q000235:genetics*; D000756:Anemia, Sideroblastic; D005838:Genotype; D006239:Haplotypes; D006451:Hemoglobin, Sickle / Q000032:analysis*; D006455:Hemoglobins, Abnormal / Q000032:analysis*; D006579:Heterozygote; D006801:Humans; D010146:Pain / Q000209:etiology; D010641:Phenotype; D055544:beta-Globins / Q000235:genetics
chemical_list: D006451:Hemoglobin, Sickle; D006455:Hemoglobins, Abnormal; D055544:beta-Globins; C026237:hemoglobin D Punjab
keywords: Bantu; haplotypes; hemoglobinopathy; hemolytic anemia; sickle cell disease