Two New β Chain Variants: Hb Tripoli [β26(B8)Glu→Ala] and Hb Tizi‐Ouzou [β29(B11)Gly→Ser]

Abstract

Two new β‐globin chain variants: Hb Tripoli: codon 26, GAG→GCG [β26(B8)Glu→Ala] and Hb Tizi‐Ouzou: codon 29, GGC→AGC [β29(B11)Gly→Ser] are described on the first exon of the β‐globin gene. The two variants are characterized by DNA sequencing and mass spectrometry (MS). Hematological abnormalities were found in the two carriers. The presence of microcytosis and hypochromia is explained by an additional homozygous 3.7 kb α⁺ thalassemic deletion for the carrier of Hb Tizi‐Ouzou. Hb Tizi‐Ouzou showed a slight instability in vitro. The same hematological abnormalities associated with anemia are difficult to explain for Hb Tripoli's carrier in the absence of an α‐globin genes abnormality and could suggest a possible abnormal splicing.

• Hb Tripoli
• Hb Tizi‐Ouzou
• β‐Globin chain variant
• Exon 1
• DNA analysis
• Mass spectrometry (MS)