MUTATION		25 bp deletion (see Fig. 3)
AMINO ACID REPLACEMENT		None
TYPE OF BETA-THAL		beta°
MECHANISM		Defective mRNA; no normal beta chain synthesis
IDENTIFICATION		Cloning or amplification of the beta-globin gene; DNA sequencing
HEMATOLOGY IN HETEROZYGOTE(S)		Hb 10.8 g/dl; MCV 74.5 fl; MCH 19.5 pg; Hb A2 5.2%; Hb F <0.5%
HEMATOLOGY IN HOMOZYGOTE(S)		The few homozygotes reported have a transfusion-dependent thalassemia major
OCCURRENCE		The Middle East; see Table IX-a
HAPLOTYPE		Not reported
FOUND IN COMBINATION WITH ABNORMAL HB(S)		Not observed
FOUND IN COMBINATION WITH BETA-THAL ALLELE(S)		Not reported
OTHER INFORMATION		None

REFERENCES
1.		Orkin, S.H., Sexton, J.P., Goff, S.C., and Kazazian, H.H., Jr.: J. Biol. Chem., 258:7249, 1983.

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This material is from the book A Syllabus of Thalassemia Mutations (1997) by Titus H.J. Huisman, Marianne F.H. Carver, and Erol Baysal, published by The Sickle Cell Anemia Foundation in Augusta, GA, USA. Copyright © 1997 by Titus H.J. Huisman. All rights reserved. Neither this work nor any part may be reproduced or transmitted in any form or by any means, electronic or mechanical, microfilming and recording, or by any information storage and retrieval systems, without permission in writing from the Author.