MUTATION		Codon 127 (A->G); CAG(Gln)->CGG(Arg)
AMINO ACID REPLACEMENT		Gln->Arg (Hb Dieppe)
TYPE OF BETA-THAL		Dominant inclusion body beta-thal trait
MECHANISM		The mutation results in the synthesis of a highly unstable betaX chain which is removed from circulation by proteolysis, causing a beta-thal condition
IDENTIFICATION		DGGE of amplified DNA fragments; sequencing
HEMATOLOGY IN HETEROZYGOTE(S)		Chronic anemia (Hb 7.5 g/dl); occasional transfusion; splenomegaly; hemosiderosis; normal Hb A2; Hb F 18.0%; beta/alpha in vitro chain ratio 0.48
HEMATOLOGY IN HOMOZYGOTE(S)		None
OCCURRENCE		In a 31-year-old French female
HAPLOTYPE		Not reported
FOUND IN COMBINATION WITH ABNORMAL HB(S)		None
FOUND IN COMBINATION WITH BETA-THAL ALLELE(S)		None
OTHER INFORMATION		Unstable Hb or betaX chain was not detected

REFERENCES
1.		Girodon, E., Ghanem, N., Vidaud, M., Riou, J., Martin, J., Galactéros, F., and Goossens, M.: Ann. Hematol., 65:188, 1992.

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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.