Abstract
BACKGROUND: Co-inheritance of β- and δ-globin mutations in Iran is not uncommon. This situation may interfere with correct diagnosis and genetic counseling of α- and β-thalassemia in screening programs. Here we report the co-inheritance of β- and δ-globin gene mutations in an individual with microcytosis, hypochromia and a normal hemoglobin A2 (HbA2) level.
METHODS: Genomic DNA extraction, amplification refractory mutation system (ARMS) polymerase chain reaction and direct DNA sequencing of δ- and β-globin genes were exploited for detection of the mutations in these two genes in an individual with low hematological indices and normal HbA2.
RESULTS: ARMS-PCR technique revealed the β+ IVSI-5 (G to C) mutation and direct DNA sequencing of the δ-globin gene detected a previously reported delta codon 12 (AAT-AAA) HbA2-NYU. This study reports HbA2-NYU in association with the β IVSI-5 (G to C) mutation in Iran.
DISCUSSION: This report emphasizes that normal HbA2 expression in a β-goblin carrier is due to mutation in the δ-globin gene and may cause misdiagnosis of thalassemia.