First Detection of Hb Taybe [α38(C3) or α39(C4) Thr→0 (α1)] in An Italian Child

• Published in: Hemoglobin 2012-06, Vol.36 (3), p.299-304
• Main Authors: Paglietti, Maria Elisabetta, Sollaino, Maria Carla, Loi, Daniela, Barella, Susanna, Desogus, Maria Franca, Galanello, Renzo
• Format: Article
• Language: English
• Subjects: alpha-Globins - genetics; Anemia, Hemolytic - genetics; Anemia, Hemolytic - pathology; Base Sequence; Child, Preschool; Chronic Disease; Codon, Initiator - genetics; DNA Mutational Analysis; Hb Taybe; Hemoglobins, Abnormal - genetics; Hemolytic anemia; Humans; Italy; Male; Mutation; Sequence Deletion; Threonine - genetics; Unstable hemoglobin (Hb); α-Thalassemia (α-thal)
• ISSN: 0363-0269; 1532-432X
• DOI: 10.3109/03630269.2012.659780

Hb Taybe [α38(C3) or α39(C4) Thr→0 (α1)] is an unstable hemoglobin (Hb) variant caused by a deletion of a threonine residue at codon 39 of the α1-globin chain. Usually asymptomatic or with minimal hematological abnormalities in the heterozygous state, Hb Taybe becomes clinically evident in compound heterozygosity with α-thalassemia (α-thal) or in homozygous patients. To date, Hb Taybe has been described in Israeli-Arab and Greek individuals. We report, for the first time, a patient with chronic hemolytic anemia due to the presence of Hb Taybe in trans to the α2 initiation codon mutation ATG>ACG in an Italian child. Hb Taybe was not evident at Hb analysis with cellulose acetate electrophoresis and high performance liquid chromatography (HPLC). Globin biosynthetic studies revealed an α β-globin ratio in the range of β-thal trait. Consequently, an investigation of the α- and β-globin genes was requested in order to avoid missing any rare globin chain variant and to offer accurate genetic counseling.