βS globin gene haplotype and the stroke risk among Egyptian children with sickle cell disease

Hematology. 2018 Jul;23(6):362-367. doi: 10.1080/10245332.2017.1403736. Epub 2017 Nov 20.

Abstract

Background and aim of work: Sickle cell disease (SCD) is an inherited disease of the beta globin gene. The βS globin gene haplotypes are Senegal, Benin, Bantu, Cameroon, Arab-Indian and atypical haplotypes. In SCD, stroke is a life-threatening event in both adults and children. In light of paucity of studies on βS globin gene haplotypes in Egypt, we aimed to determine βS globin gene haplotypes in children with SCD and study their impact on stroke risk.

Methods: Fifty-two SCD patients were included in the study, they were 26 males and 26 females with age range from 3 to 18 years old. The PCR-RFLP technique was used for the determination of βS globin gene haplotypes. Transcranial Doppler (TCD) was done to identify patients at risk of stroke.

Results: Benin/Benin was the most prevalent haplotype detected in 50% followed by Benin/Bantu in 30.8% of studied patients. TCD study showed that 14/52 (26.9%) patients had abnormally high TCD flow velocities (TCD velocities ≥170 cm/s) and thus considered high stroke risk group, whereas 38/52 (73.1%) patients had TCD flow velocities <170 cm/s and are considered low stroke risk group. Stroke risk was not found to be associated with βS globin gene haplotype (p = .532).

Conclusion: This study provides a relevant contribution to our understanding of the anthropological and historical background of the population in Egypt where Benin haplotype is the commonest βS globin gene haplotype and homozygous Benin/Benin is associated with higher stroke risk than other haplotypes.

Keywords: Benin; Egypt; Sickle cell disease; TCD; bantu; stroke; β S globin; β s haplotype.

MeSH terms

  • Adolescent
  • Alleles
  • Anemia, Sickle Cell / blood
  • Anemia, Sickle Cell / complications*
  • Anemia, Sickle Cell / diagnosis
  • Anemia, Sickle Cell / genetics*
  • Child
  • Child, Preschool
  • Egypt / epidemiology
  • Female
  • Gene Frequency
  • Haplotypes*
  • Hemoglobin, Sickle / genetics
  • Humans
  • Male
  • Risk Assessment
  • Risk Factors
  • Stroke / epidemiology*
  • Stroke / etiology*
  • beta-Globins / genetics*

Substances

  • Hemoglobin, Sickle
  • beta-Globins