Phenotypic effect of α-globin gene numbers on Indian sickle β-thalassemia patients

J Clin Lab Anal. 2014 Mar;28(2):110-3. doi: 10.1002/jcla.21652. Epub 2014 Jan 6.

Abstract

Background: Sickle cell β-thalassemia is a compound heterozygous state of β-thalassemia and sickle cell anemia. Patient with these conditions showed mild-to-severe clinical phenotype.

Objectives: The objective of this study was to evaluate the effects of α-globin gene numbers on the phenotype of sickle cell β-thalassemia patients.

Materials and methods: Seventy-five sickle cell β-thalassemia patients were characterized. Clinical, hematological, and molecular characterization was performed in all subjects. Amplified refectory mutation system-polymerase chain reaction was applied for β-thalassemia mutation study while α-genotyping was conducted by Gap-PCR.

Results: Highest frequency of IVS1-5 (33 out of 75 patients) β-thalassemia genotype was recorded. Twenty-eight patients were reported with α-globin chain deletion while four had α-triplications (Anti α-3.7kb). Sickle β-thalassemia patients with α-chain deletions ameliorate hematological and clinical variables.

Conclusions: This study indicates that the coexistence of α-globin chain deletions showed mild phenotype instead of absence of α-chain deletions while the patients with triplication of α-genes express severe phenotype.

Keywords: ARMS-PCR; Gap-PCR; SCD; sickle β-thalassemia; α-thalassemia.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Anemia, Sickle Cell / complications
  • Anemia, Sickle Cell / genetics*
  • Anemia, Sickle Cell / pathology*
  • Child
  • Female
  • Gene Dosage*
  • Humans
  • India
  • Male
  • Phenotype
  • alpha-Globins / genetics*
  • beta-Thalassemia / complications
  • beta-Thalassemia / genetics*
  • beta-Thalassemia / pathology*

Substances

  • alpha-Globins