Journal of Hematology, ISSN 1927-1212 print, 1927-1220 online, Open Access
Article copyright, the authors; Journal compilation copyright, J Hematol and Elmer Press Inc
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Case Report

Volume 11, Number 5, October 2022, pages 190-195

Hemoglobin Alpha Chain Variant Zara Associated With Familial Asymptomatic Hypoxemia

Figures

Figure 1.
Figure 1. Hemoglobin (a) capillary zone electrophoresis and (b) HPLC results in the father and daughter described in this case, demonstrating an increase in variant fractions resolved on HPLC. HPLC: high-performance liquid chromatography.
Figure 2.
Figure 2. (a) Locations of Hb Zara within the HbA2 locus on the short arm of chromosome 16 [7]. (b) Representative DNA sequencing of the alpha 2 globin gene exon 2 locus. Vertical blue bars represent stronger probability, while the yellow bars represent weaker probability of results. The dark red horizontal lines indicate no match where the mutation is, which indicates a C>A missense mutation. Hb: hemoglobin.

Table

Table 1. Pertinent Laboratory Findings in the Father and Daughter Described in This Case
 
Father (age 36)aDaughter (age 14)a
aNormal ranges are shown in parentheses. HPLC: high-performance liquid chromatography.
Complete blood count
  White blood cell count (× 103/µL)5.0 (4.2 - 9.1)6.0 (4.5 - 13)
  Red blood cell count ((× 106/µL)4.5 (4.6 - 6.0)3.63 (3.8 - 5.1)
  Hemoglobin (g/dL)12.8 (13.7 - 17.5)10.9 (11.5 - 15.3)
  Hematocrit (%)41.2 (40 - 51)32.8 (34 - 46)
  Mean corpuscular volume (fL)91.6 (79 - 92)90.4 (78 - 98)
  Platelet count (× 103/µL)314 (150 - 400)219 (140 - 400)
Hemoglobin HPLC
  Hemoglobin A (%)80.7 (> 96)80.6 (> 96)
  Hemoglobin A2 (%)2.3 (1.8 - 3.5)2.4 (1.8 - 3.5)
  Hemoglobin F (%)0.0 (< 2.0)0.0 (< 2.0)
  Hemoglobin variant (%)17 (0)17 (0)