The T gamma chain of human fetal hemoglobin at birth and in several abnormal hematologic conditions.
The T gamma chain of human fetal hemoglobin has a threonyl in stead of an isoleucyl residue in position 75. When the cord bloods from infants from varied ethnic backgrouds and geographic areas were tested for the presence of the T gamma chain, it was present in 28 or 98 samples. In some groups as many as 40% had the T gamma chain whereas none was detected in other. When the T gamma chain was present, its quantity was about 20% of the total gamma chains, but one case had 35%. Among beta-thalassemia homozygotes of the Mediterranean region, 70% and the T gamma chain in the amount of 20-50% of the total gamma chains, but seven Black beta-thalassemia homozygotes were negative for the T gamma chain. The fetal hemoglobin of 16 adult patients with sickle cell anemia had no T gamma chains, but 2 of 9 newborn children with sickle cell anemia had the T gamma chain. The frequency of the T gamma gene (16), the relationship of the T gamma gene to the G gamma and A gamma genes, and the significance of the T gamma gene are discussed.
D000328:Adult; D000596:Amino Acids / Q000032:analysis; D000745:Anemia, Hemolytic, Congenital / Q000097:blood* / Q000235:genetics; D055598:Chemical Phenomena; D002621:Chemistry; D002852:Chromatography, Ion Exchange; D005312:Fetal Blood / Q000032:analysis; D005319:Fetal Hemoglobin / Q000235:genetics; D005787:Gene Frequency; D006801:Humans; D006868:Hydrolysis; D007231:Infant, Newborn; D044469:Racial Groups
D000596:Amino Acids; D005319:Fetal Hemoglobin