Hemoglobin alpha chain deficiency in black children with variable quantities of hemoglobin Bart's at birth

Pediatric Research
|February 1, 1977
PubMed

Insights

This study investigated alpha-thalassemia in children, finding that higher levels of Hemoglobin Bart's at birth correlate with decreased red blood cell size and hemoglobin content, indicating a familial alpha chain deficiency.

Area of Science:

  • Genetics
  • Hematology

Background:

  • Alpha-thalassemia is a genetic blood disorder characterized by reduced or absent synthesis of alpha-globin chains.
  • It can lead to various clinical presentations, from asymptomatic carriers to severe anemia.

Purpose of the Study:

  • To investigate the hematologic findings and globin chain synthesis in children with varying levels of Hemoglobin Bart's (Hb Bart's) at birth.
  • To determine the familial inheritance pattern of alpha chain deficiency.

Main Methods:

  • Hematologic studies including mean corpuscular volume (MCV) and mean corpuscular hemoglobin (MCH) were performed.
  • Globin chain synthesis analysis was conducted on 21 children (aged 2-6 years), their parents, and controls.
  • Beta/alpha globin chain synthesis ratios were calculated.

Main Results:

  • Children with approximately 5% Hb Bart's at birth showed significantly decreased MCV and MCH, and increased beta/alpha ratios.
  • Children with 2% Hb Bart's had increased beta/alpha ratios but lacked microcytosis and hypochromia.
  • Alpha chain deficiency was found to be familial, with some parents exhibiting increased alpha/alpha ratios and suggestive hematologic findings.

Conclusions:

  • Elevated Hb Bart's levels at birth are associated with specific hematologic changes indicative of alpha chain deficiency.
  • The observed alpha chain deficiency demonstrates a familial inheritance pattern.
  • The study highlights the utility of Hb Bart's levels at birth as an indicator of alpha-thalassemia severity and inheritance.

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