Human embryonic zeta-globin chain expression in deletional alpha-thalassemias.
zeta-Globin chain expression in carriers of a number of deletional alpha-thalassemias is investigated by radioimmunoassay. In a few cases, zeta-globin mRNAs are also studied. zeta-Globin chains are detected in (--SEA/), (--MED/), and (--SPAN/) deletions, but not in six other deletional mutations. These results suggest that the DNA element capable of suppressing zeta-globin expression in adult erythroid cells is present within the (--SPAN/) deletion, while the DNA fragment between the 5' breakpoints of the (--SA/) and the (--SEA/) deletions may contain sequences necessary for augmenting zeta-globin expression in adult erythroid cells. Furthermore, zeta-globin chains are shown by an immunocytologic technique to be present in all circulating erythrocytes in carriers of the (--SEA/) and (--MED/) deletions. This simple immunocytologic test is highly sensitive and specific to detect adult carriers of either the (--SEA/) or (--MED/) deletions, and can be used for the detection of couples at risk of pregnancies involving fetuses with homozygous alpha-thalassemia.
Tang
W
W
Department of Pathology, McMaster University, School of Medicine, Hamilton, Ontario, Canada.
Luo
H Y
HY
Albitar
M
M
Patterson
M
M
Eng
B
B
Waye
J S
JS
Liebhaber
S A
SA
Higgs
D R
DR
Chui
D H
DH
D002872:Chromosome Deletion; D004247:DNA / Q000097:blood / Q000235:genetics / Q000302:isolation & purification; D004622:Embryo, Mammalian; D004912:Erythrocytes / Q000378:metabolism; D015870:Gene Expression; D006580:Genetic Carrier Screening; D014644:Genetic Variation; D005914:Globins / Q000235:genetics*; D006801:Humans; D005810:Multigene Family; D016133:Polymerase Chain Reaction / Q000379:methods; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D012156:Reticulocytes / Q000378:metabolism; D013789:Thalassemia / Q000097:blood / Q000235:genetics*
D012333:RNA, Messenger; D005914:Globins; D004247:DNA