Molecular and hematological characterization of HbE heterozygote with alpha-thalassemia determinant.
Hemoglobin E and alpha-thalassemia are prevalent in Thailand. The chance that an individual heterozygous for HbE also carries an alpha-thalassemia determinant is high. In this individual, the amount of HbE and other hematological parameters may be differed from that of usual observation. In this study, a total of 132 HbE heterozygotes were screened for alpha-thalassemia 1 gene deletion by the polymerase chain reaction. Out of 132 cases, 71 could be completely analyzed for hematologic parameters. Forty-three of 88 cases with HbE less than 25% as measured using microcolumn chromatography were positive for this gene deletion. In twenty of these 43 alpha-thalassemia 1 positive cases, the average values of Hb, Hct, MCV, MCH, MCHC, RDW and HbE were 10.6 g/ dl, 33.1%, 64.8 fl, 21.0 pg, 32.3 pg/dl, 18.6% and 17.4%, respectively. Eight of 9 alpha-thalassemia 1 negative cases were positive for alpha-thalassemia 2 gene deletion in Southern blot analysis. In this later group, hematological parameters were similar to that of the former. Co-inheritance of the Hb Constant Spring gene has no direct effect on the level of HbE. No alpha-thalassemia 1 gene was detected in the remaining 34 cases whose HbE were above 25%. The average amount of Hb, Hct, MCV, MCH, MCHC, RDW and HbE were 12.4 g/dl, 37.7%, 79.7 fl, 26.2 pg, 32.7 pg/dl, 25.8% and 28.5%, respectively. Therefore, screening for HbE level below 25% may be a convenient way of identifying parents of carrying alpha-thalassemia 1 determinant.
Sanchaisuriya
K
K
Department of Clinical Microscopy, Faculty of Associated Medical Sciences, Khon Kaen University, Thailand.
Fucharoen
G
G
Sae-ung
N
N
Sae-ue
N
N
Baisungneon
R
R
Jetsrisuparb
A
A
Fucharoen
S
S
D004912:Erythrocytes / Q000502:physiology; D006446:Hemoglobin E / Q000235:genetics*; D006579:Heterozygote; D006801:Humans; D013785:Thailand; D017085:alpha-Thalassemia / Q000235:genetics*
D006446:Hemoglobin E