title: Thalassemia-like phenotype in a novel complex hemoglobinopathy with α, β, δ globin chain abnormalities.
abstract: The occurrence of multiple abnormalities of α, β, δ, and γ globin genes may lead to unusual and complex phenotypes when they arise simultaneously in the same individual. Here, we report the findings of an African American boy who coinherited 3 heterozygous globin gene abnormalities: the unstable β-globin chain variant; hemoglobin (Hb) Showa-Yakushiji [β110(G12) Leu→Pro], the δ-globin chain variant; HbB2 [δ16(A13) Gly→Arg] and α-thalassemia (α-thal); (α-/αα). Hb Showa-Yakushiji had been previously described in Japanese, Indian, and European populations. We report its first occurrence in a child of African ancestry who presented with anemia not responsive to iron and an incomplete β-thalassemia minor phenotype. Although the clinical and laboratory features of Hb Showa-Yakushiji mimic those of a β-thalassemia, the coinheritance of the δ-globin chain variant Hb B2 suppressed the relative increase in Hb A2 usually observed in heterozygotes for the Hb Showa-Yakushiji mutation. Protein-based methods detected only a trace amount of HbB2 and failed to reveal presence of Hb Showa-Yakushiji and α-thal. The latter were only identified through DNA analyses. The diagnostic difficulties, molecular characteristics, and genotype/phenotype correlations of this novel complex hemoglobinopathy syndrome are reviewed.
authors: Department of Pediatrics, Wake Forest University School of Medicine, Winston-Salem, NC, USA.
authors: Hernan
authors: H
authors: Sabio
authors: Natalia
authors: N
authors: Dixon
authors: Niren
authors: N
authors: Patel
authors: Chinwe
authors: C
authors: Obiaga
authors: Lina
authors: L
authors: Zhuang
authors: Steffen E
authors: SE
authors: Meiler
authors: Abdullah
authors: A
authors: Kutlar
authors: Ferdane
authors: F
authors: Kutlar
mesh_terms: D001741:Black or African American / Q000235:genetics; D000740:Anemia / Q000209:etiology / Q000235:genetics*; D002675:Child, Preschool; D006455:Hemoglobins, Abnormal / Q000235:genetics*; D006579:Heterozygote; D006801:Humans; D008297:Male; D010641:Phenotype; D017085:alpha-Thalassemia / Q000097:blood / Q000150:complications / Q000235:genetics*; D017086:beta-Thalassemia / Q000097:blood / Q000150:complications / Q000235:genetics*; D055538:delta-Thalassemia / Q000150:complications / Q000235:genetics*
chemical_list: D006455:Hemoglobins, Abnormal; C502559:hemoglobin Showa-Yakushiji