title: Hb Dartmouth (HBA2: c.200T>C): An α2-Globin Gene Associated with Hb H Disease in One Homozygous Patient.
abstract: Hb H (β4) disease is caused by deletion or inactivation of three out of four α-globin genes. A high incidence of Hb H disease has been reported all over the world. There is a wide spectrum of phenotypic presentations, from clinically asymptomatic to having significant hepatosplenomegaly and requiring occasional or even regular blood transfusions, even more severe anemia, Hb Bart's (γ4) hydrops fetalis syndrome that can cause death in the affected fetuses late in gestation. We here present a case who was diagnosed with Hb H disease that represents a new genotype for this hereditary disorder. Hb Dartmouth is a variant caused by a missense mutation at codon 66 of the α2-globin gene (HBA2: c.200T>C), resulting in the substitution of leucine by proline. We here emphasize the importance of this point mutation involving Hb H disease and also the necessity for prenatal diagnosis (PND) for those who carry this point mutation in the heterozygous state.
authors.affiliation: Kariminejad-Najmabadi Pathology & Genetics Center , Tehran , Iran .
authors.forename: Samaneh
authors.initials: S
authors.lastname: Farashi
authors.forename: Negin
authors.initials: N
authors.lastname: Faramarzi Garous
authors.forename: Mehri
authors.initials: M
authors.lastname: Ashki
authors.forename: Shadi
authors.initials: S
authors.lastname: Vakili
authors.forename: Fatemah
authors.initials: F
authors.lastname: Zeinali
authors.forename: Hashem
authors.initials: H
authors.lastname: Imanian
authors.forename: Azita
authors.initials: A
authors.lastname: Azarkeivan
authors.forename: Hossein
authors.initials: H
authors.lastname: Najmabadi
mesh_terms: D000328:Adult; D000483:Alleles; D002675:Child, Preschool; D003241:Consanguinity; D004909:Erythrocyte Indices; D005260:Female; D006447:Hemoglobin H / Q000235:genetics; D006453:Hemoglobinopathies / Q000097:blood / Q000175:diagnosis / Q000235:genetics*; D006455:Hemoglobins, Abnormal / Q000235:genetics*; D006720:Homozygote; D006801:Humans; D008297:Male; D017354:Point Mutation; D055542:alpha-Globins / Q000235:genetics
chemical_list: D006455:Hemoglobins, Abnormal; D055542:alpha-Globins; D006447:Hemoglobin H
keywords: Hb Bart’s hydrops fetalis; Hb Dartmouth; Hb H disease; hepatosplenomegaly; α-Thalassemia (α-thal)