Hematologic indices of the proband and his parents
| . | Sex . | Hb, g/dL . | MCV, fL . | MCH, pg . | RBC, ×1012 cells per L . | HbH inclusions . | Genotype . | Phenotype . |
|---|---|---|---|---|---|---|---|---|
| A.F., unaffected father | M | 15.9 | 89.1 | 29.4 | 5.4 | − | αα/αα | normal |
| H.F., affected mother | F | 12.6 | 73.6 | 22.2 | 5.67 | + | ααα/α-ZF | α-thalassemia trait |
| Z.F., proband | M | 12.6 | 67.8 | 21.6 | 5.84 | + | αα/α-ZF | α-thalassemia trait |
| . | Sex . | Hb, g/dL . | MCV, fL . | MCH, pg . | RBC, ×1012 cells per L . | HbH inclusions . | Genotype . | Phenotype . |
|---|---|---|---|---|---|---|---|---|
| A.F., unaffected father | M | 15.9 | 89.1 | 29.4 | 5.4 | − | αα/αα | normal |
| H.F., affected mother | F | 12.6 | 73.6 | 22.2 | 5.67 | + | ααα/α-ZF | α-thalassemia trait |
| Z.F., proband | M | 12.6 | 67.8 | 21.6 | 5.84 | + | αα/α-ZF | α-thalassemia trait |
All family members are adults. The normal hemoglobin range for females is 13.0-15.0 g/dL and for males, 14.6-16.6 g/dL. The normal mean red cell volume (MCV) range is 85.0-95.0 fL. The normal mean red cell hemoglobin (MCH) range is 30 ± 2.0 pg. Note that the typical values for patients with the Mendelian forms of α-thalassemia with three α genes (−α/αα) is 26.2 ± 2.3 pg, and the values for two α genes (−−/αα) are 21.7 ± 1.7 pg.54 The normal total red blood cell (RBC) range for females is 4.2-4.9 × 1012 cells per L and for males, 4.9-5.6 × 1012 cells per L. Rare hemoglobin H (HbH) inclusions are almost exclusively seen in patients who have α-thalassemia with only two α genes (αα/−−) rather than three α genes (−α/ααα).54 Chromosomes with 3 α genes (ααα) are a common polymorphic variant. Expression of α-globin from such chromosomes is similar to that from normal (αα) chromosomes.54