title: Homozygous Hb Stanleyville-II [alpha2 78(EF7) Asn>Lys; HBA2:c.237C>A, not C>G] associated with genotype -α 3.7/-α 3.7 in two Brazilian families.
abstract: BACKGROUND
  Several hemoglobin variants have electrophoretic behavior similar to hemoglobin S, which may lead to false diagnosis for sickle-cell disorders in newborn screening programs. A homozygous hemoglobin with S mobility was detected in two unrelated babies in Brazil.
  
  
  METHODS
  Isoelectric focusing and high-performance liquid chromatography assays, gene sequencing, and restriction fragment length polymorphism with AfeI were used to characterize the hemoglobin.
  
  
  RESULTS
  Hb Stanleyville-II and -α(3.7) /-α(3.7) type I deletion in the α-globin gene was diagnosed. Parents were heterozygous for both Hb Stanleyville-II and α-thalassemia. Hypochromia and microcytosis were probably due to the homozygous α-thalassemia.
  
  
  CONCLUSIONS
  Stanleyville-II gene mutation is HBA2:c.237C>A, or C>G, and this information on the Globin Gene Server should be updated; AfeI test is a fast and accurate method to detect it; NBS programs should consider the possibility of Hb Stanleyville-II whenever IEF shows one band in the HbS position, and another one between S and C.
authors.affiliation: Núcleo de Ações e Pesquisa em Apoio Diagnóstico (Nupad), Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, Brazil.
authors.forename: F S
authors.initials: FS
authors.lastname: Pimentel
authors.forename: M R
authors.initials: MR
authors.lastname: Silva
authors.forename: M H C
authors.initials: MH
authors.lastname: Ferraz
authors.forename: N O
authors.initials: NO
authors.lastname: Carvalho
authors.forename: C
authors.initials: C
authors.lastname: Perone
authors.forename: D Méndez
authors.initials: DM
authors.lastname: del Castillo
authors.forename: J N
authors.initials: JN
authors.lastname: Januario
authors.forename: M B
authors.initials: MB
authors.lastname: Viana
mesh_terms: D001483:Base Sequence; D001938:Brazil; D004252:DNA Mutational Analysis; D005192:Family Health; D005838:Genotype; D006455:Hemoglobins, Abnormal / Q000235:genetics*; D006720:Homozygote; D006801:Humans; D007231:Infant, Newborn; D008969:Molecular Sequence Data; D020125:Mutation, Missense; D055542:alpha-Globins / Q000235:genetics*; D017085:alpha-Thalassemia / Q000235:genetics*
chemical_list: D006455:Hemoglobins, Abnormal; D055542:alpha-Globins; C037389:hemoglobin Stanleyville II