title: The development of haemoglobin A2 in normal negro infants and in sickle cell disease.
abstract: The development of haemoglobin A2 levels from birth to 3 years has been compared in normal, beta-thalassaemia trait, sickle cell (SS) disease, and S-beta-thalassaemia genotypes. Hb A2 levels were almost identical in normals and in children with SS disease at 1, 2 and 3 years. The most rapid increases in Hb A2 levels occurred before 6 months but levels were still rising at the end of the third year. Sickle cell-beta+ thalassaemia could be differentiated from SS disease by the higher Hb A2 levels between 6 months and 1 year. Insufficient data were available on S-beta o thalassaemia but since Hb A2 levels in this condition are generally higher than those in S-beta+ thalassaemia, differentiation from SS disease may may also be possible from the age of 6 months.
mesh_terms: D000367:Age Factors; D000755:Anemia, Sickle Cell / Q000097:blood*; D044383:Black People; D002675:Child, Preschool; D006441:Hemoglobin A / Q000096:biosynthesis*; D006454:Hemoglobins / Q000096:biosynthesis*; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007563:Jamaica; D011446:Prospective Studies; D012805:Sickle Cell Trait / Q000097:blood*; D013789:Thalassemia / Q000097:blood*
chemical_list: D006454:Hemoglobins; D006441:Hemoglobin A