Haplotype Analysis of Three Common β-Thalassemia Mutations in Syrian Patients

Abstract

β-Globin haplotypes were used to investigate the origin of three common β-globin mutations, IVS-I-110 (G>A); HBB: c.93-21G>A, IVS-I-1 (G>A); HBB: c.92 + 1G>A and codon 39 (C>T); HBB: c.118C > T in Syrian patients. Haplotype analysis was done for 49 unrelated patients with β-thalassemia (β-thal) and 20 unrelated healthy subjects by polymerase chain reaction (PCR)-based restriction fragment length polymorphism (RFLP) for the β-globin gene cluster of the following polymorphic restriction sites: HincII 5' to ε, HindIII 5' to ^Gγ, HindIII 5' to ^Aγ, HincII in ψβ, HincII 3' to ψβ, AvaII in β, and HinfI 3' to β. The IVS-I-110 mutation was associated with three haplotypes: I [+ – – – – + +] (79.4%), V [+ – – – – + –] (5.9%) and VII [+ – – – – – +] (14.7%), while, the two mutations IVS-I-1 and codon 39 were be linked to a single haplotype V (100.0%) and II [– + + – + + +] (100.0%), respectively. The normal chromosomes (β^A/β^A) were associated with four haplotypes, I (50.0%), II (7.5%), V (32.5%) and VII (10.0%). In the Syrian population, the IVS-I-110 mutation was associated with multi haplotypes, whereas the IVS-I-1 and codon 39 mutations have a single origin. More studies for the other mutations will be very useful for genetic epidemiological studies in Syria.

Keywords:

• Haplotype(s)
• β-thalassemia (β-thal)
• common mutations
• Syria

Acknowledgments

We thank Professor I. Othman, Director General of Atomic Energy Commission of Syria (AECS) and Dr. N. Mirali, the head of the Molecular Biology and Biotechnology Department for their support. We also thank Mr. R. Aboz and Ms. S. Tez for their help in collecting the samples from the patients.

Disclosure statement

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

Additional information

Funding

This study was supported by the Atomic Energy Commission of Syria.