title: Organization of the alpha-globin genes in the Chinese alpha-thalassemia syndromes.
abstract: The alpha-thalassemia syndromes are a group of inherited anemias, the clinical severity of which has been shown to increase with the number of alpha-globin structural genes deleted. Employing restriction endonuclease gene mapping, we defined the organization of the alpha-globin genes in cellular DNA from Chinese subjects with various alpha-thalassemia syndromes. The four alpha-globin genes of normals are at two loci located on a 23.0-kilobase pair (kb) Eco RI fragment. In deletion type hemoglobin-H disease the 5' alpha-globin locus is deleted and the single 3' alpha-globin locus is found on a 19.0-kb Eco RI fragment. In alpha-thalassemia-2 there are two alpha-globin genes on a 23.0-kb Eco RI fragment and one on a 19.0-kb fragment. In alpha-thalassemia-1 and the nondeletion type of hemoglobin-H disease the two alpha-globin genes are at two loci on one chromosome and none reside on the other chromosome.
mesh_terms: D002681:China; D002872:Chromosome Deletion; D002874:Chromosome Mapping; D004247:DNA / Q000235:genetics; D004262:DNA Restriction Enzymes; D005796:Genes; D005914:Globins / Q000235:genetics*; D006801:Humans; D013577:Syndrome; D013789:Thalassemia / Q000235:genetics*
chemical_list: D005914:Globins; D004247:DNA; D004262:DNA Restriction Enzymes