MUTATION		Codon 115 (C->A); GCC(Ala)->GAC(Asp)
AMINO ACID REPLACEMENT		Ala->Asp (Hb Hradec Kralove or Hb HK)
TYPE OF BETA-THAL		beta+ (dominant beta-thal trait)
MECHANISM		The mutation results in the synthesis of a severely unstable Hb variant which is readily catabolized in red cell precursors
IDENTIFICATION		Amplification of the beta-globin gene; sequencing of amplified DNA; dot-blot analysis with allele specific probes; AvaII digestion
HEMATOLOGY IN HETEROZYGOTE(S)		Mother and daughter have a moderate anemia; reticulocytosis; nucleated red cells, Heinz body formation; splenomegaly (one subject is splenectomized)
		Sex-Age Hb g/dl MCV fl MCH pg A2 % F % F-32 9.6 91.4 28.5 4.2 4.0 F-6 9.8 79.6 25.5 3.2 13.4
HEMATOLOGY IN HOMOZYGOTE(S)		Not reported
OCCURRENCE		In a small Czech family
HAPLOTYPE		Not determined
FOUND IN COMBINATION WITH ABNORMAL HB(S)		See above
FOUND IN COMBINATION WITH BETA-THAL ALLELE(S)		See above
OTHER INFORMATION		The variant cannot be detected by electrophoretic or chromatographic procedures; instability tests are slightly positive only in red cell lysates from freshly collected blood; Heinz bodies likely contain mainly alpha chains

REFERENCES
1.		Divoky, V., Svobodova, M., Indrak, K., Chrobak, L., Molchanova, T.P., and Huisman, T.H.J.: Hemoglobin, 17:319, 1993.

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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.