Determination of the gamma G/gamma A ratio in homozygous beta-thalassemic patients among a Lebanese population.
The gamma G/gamma A ratio was determined on 50 cord blood samples from normal newborns and in 28 beta-thalassemia homozygotes among the Lebanese population, using electrophoresis on acrylamide-bisacrylamide gels containing Triton X-100, urea, and 2-mercapto-ethanol. 2-Mercapto-ethanol was found to be the most effective reducer, giving good resolution and a clean background. As the concentration of Triton X-100 was critical in this study, a concentration of 500 microliters of Triton X-100/25 ml of reaction mixture was found to be optimal. In our 50 cord blood samples, the mean total Hb was 20 g/dl, with a range of 12-26. The mean fetal Hb (HbF) level was 64%, and the range 50-90%. The mean value for gamma G/gamma G + gamma A was 0.75. All beta-homozygotes had an elevated HbF, ranging from 7.7-99.3%, and their mean gamma G/gamma G + gamma A was 0.64. Only two out of 28 had gamma G/gamma G + gamma A ratio of 0.5; in the rest it was 0.60 or greater. This may be due to the greater resistance of erythrocytes with higher HbF and higher gamma G/gamma A destruction.
D004591:Electrophoresis, Polyacrylamide Gel; D005312:Fetal Blood / Q000032:analysis; D005319:Fetal Hemoglobin / Q000032:analysis*; D006720:Homozygote; D006801:Humans; D007231:Infant, Newborn; D007861:Lebanon; D013789:Thalassemia / Q000097:blood* / Q000235:genetics
D005319:Fetal Hemoglobin