MUTATION		Codon 98 (GTG->ATG)
AMINO ACID REPLACEMENT		Val->Met; Hb A2-Wrens
TYPE OF DELTA-THAL		delta+
MECHANISM		Formation of an unstable Hb comparable to Hb Köln [beta98(FG5)Val->Met]
IDENTIFICATION		Amplification of the delta-globin gene; DNA sequencing; dot-blot analysis with mutation specific probes
% HB A2 IN HETEROZYGOTE(S)		Hb A2 was determined by cation exchange HPLC; Hb A2 0.8% in heterozygote; the proband was compound heterozygote for the Black HPFH (deletion of the beta+delta genes) and Hb A2-Wrens; his Hb A 2 was 0.5% which decreased upon storage
% HB A2 IN HOMOZYGOTE(S)		Not observed
OCCURRENCE		In a Black family
HAPLOTYPE		Not determined
FOUND IN COMBINATION WITH ABNORMAL HB(S)		None
FOUND IN COMBINATION WITH DELTA-THAL ALLELE(S)		None
OTHER INFORMATION		None

REFERENCES
1.		Codrington, J.F., Kutlar, F., Harris, H.F., Wilson, J.B., Stoming, T.A., and Huisman, T.H.J.: Biochim. Biophys. Acta, 1009:87, 1989.

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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.