Longitudinal-Study Of A Newborn With A Combination Of Deletion And Nondeletion Alpha-Thalassemia-2

In this study we have characterized by DNA analysis the molecular basis of an alpha-thalassemia condition found in an infant, with 16% Hb Bart's at birth, who developed an hematologic picture similar to the alpha-thalassemia carrier state. Restriction endonuclease analysis and hybridization with alpha and zeta specific probes have provided strong evidence that this patient carries a genetic compound of deletion alpha-thalassemia-2 lesion (-alpha) and a non-deletion defect [(alpha alpha)th] with both alpha-structural genes intact on chromosome 16. He inherited the deletion alpha-thalassemia-2 chromosome (-alpha) from the father and the chromosome with non-deletion alpha-thalassemia defect from the mother. Because the deletion of one, two, or three alpha-globin structural genes is associated with 1-2%, 5-6%, or 25%, Hb Bart's respectively, these findings suggest that the non-deletion chromosome [(alpha alpha)th] contains two alpha-globin structural genes that are less active than a single alpha gene (-alpha).