TITLE:
Co-Inheritance of Beta & Delta-Globin Gene (HbYialousa) Mutations in an Iranian β-Thalassemia Carrier
AUTHORS:
Atefeh Valaei, Farnaz Eghbalpour, Zahra Kainimoghaddam, Fatemeh Bayat, Maryam Taghavi Basmanj, Morteza Karimipoor, Sirous Zeinali
KEYWORDS:
δ-Globin Gene; β-Thalassemia; HbYialousa; β-Globin Gene; CD39
JOURNAL NAME:
International Journal of Clinical Medicine,
Vol.3 No.7,
December
31,
2012
ABSTRACT: Introduction: Beta-thalassemia is characterized by
absence or reduced synthesis of the β-globin.
Carriers of β-thalas- semia,
typically have microcytic hypochromic anemia and elevated hemoglobin HbA2 and normal HbF level. On the other hand carriers of severe alpha-thalassemia
also have similar CBC parameters to that of β-thalassemia
with normal HbA2 level. Co-presence of mutations in the β-globin and delta-globin genes (point
mutations or deletions) usually give normal HbA2 and elevated HbF
level. We report a β-thal carrier
with normal level of HbA2 and increased level of HbF who had a point
mutation in CD39 on the beta-globin gene and a point mutation in CD27 on the δ-globin gene named Hb-Yialousa. Materials & Methods: An individual with low hematological
indices, normal HbA2 and elevated HbF was referred to our center as
routine premarital screening program. Mutations in the β-globin and δ-globin
genes were screened using ARMS and sequencing methods. Results: The mutation in β-
and δ-globin
genes were identified as CD39 and CD27 (HbYialousa) respectively.
No point mutation or deletion in α-globin
gene was identified. Discussion: We showed that normal HBA2 with
elevated HbF level is due to co-inheritance of delta-globin gene mutation with
mutation in the β-globin gene. When
screening for β-thalassemia, one has
to either rule out presence of α-globin
gene mutation of mutation in the delta-globin gene.