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).
D002675:Child, Preschool; D002872:Chromosome Deletion; D002902:Chromosomes, Human, 16-18; D004247:DNA / Q000235:genetics; D004262:DNA Restriction Enzymes / Q000032:analysis; D004912:Erythrocytes / Q000032:analysis; D005500:Follow-Up Studies; D005796:Genes; D006580:Genetic Carrier Screening; D005914:Globins / Q000235:genetics; D006441:Hemoglobin A / Q000032:analysis; D006447:Hemoglobin H / Q000032:analysis; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D009693:Nucleic Acid Hybridization; D013789:Thalassemia / Q000097:blood / Q000175:diagnosis / Q000235:genetics*
D005914:Globins; D004247:DNA; D006441:Hemoglobin A; D006447:Hemoglobin H; D004262:DNA Restriction Enzymes