Interaction of Hb Adana (HBA2: c.179G>A) with Deletional and Nondeletional α⁺-Thalassemia Mutations: Diverse Hematological and Clinical Features

Abstract

We describe 27 cases of mild-to-severe α-thalassemia (α-thal) syndrome caused by interaction of Hb Adana [α59(E8)Gly→Asp, GGC>GAC (α2)] with deletional and nondeletional α⁺-thal mutations in Indonesian patients. Hematological profiles and clinical manifestations of all patients were assessed by routine procedures. The genotypes were generated by a multiplex-polymerase chain reaction (m-PCR), PCR-RFLP (restriction fragment length polymorphism)-based method, and DNA sequencing. The α-thal patients who had Hb Adana in combination with the 3.7 kb deletion mostly have mild-to-moderate anemia. In contrast, patients who were compound heterozygotes for Hb Adana and nondeletional mutations, generally showed a more severe anemia and it mostly presented in childhood. Thus, accurate diagnosis of α-thal disorders is not only important for future management of these patients but also for providing proper genetic counseling to the family.

• Hb Adana
• Hematological features
• α-Thalassemia (α-thal) mutations

ACKNOWLEDGMENTS

The authors thank Professor Suthat Fucharoen, (Thalassemia Research Center, Institute of Molecular Biosciences, Mahidol University, Salaya Campus, Thailand) for valuable comments, suggestions and proofreading the manuscript; our thanks also to Dr. Trevor Jones for proofreading the manuscript. The authors also thank Dr. Pustika A Wahidiyat and Teny T Sari from the Department of Child Health, Cipto Mangunkusumo Hospital, Jakarta; Dr. Dasril Daud from the Department of Child Health, Medical Faculty, Hasanuddin University, Makassar, Intan Russianna from Gatot Subroto Hospital, Jakarta; Udjiani E. Pawitro from Tangerang Regional General Hospital, Tangerang, Banten, for referring the patients.

Declaration of Interest: The authors report no conflicts of interest. The authors alone are responsible for the content and writing of this article.