MUTATION		Codon 64 (-G); GGC(Gly)->-GC
AMINO ACID REPLACEMENT		None
TYPE OF BETA-THAL		beta°
MECHANISM		The loss of a G from codon 64 changes the reading frame with a stop codon at codon 88 resulting in a premature termination of translation
IDENTIFICATION		Cloning of the beta-globin gene; DNA sequencing; amplification and sequencing
HEMATOLOGY IN HETEROZYGOTE(S)		Hb A2 5.4%; Hb F 1.8%; beta/alpha ratio 0.34
HEMATOLOGY IN HOMOZYGOTE(S)		None
OCCURRENCE		In a Swiss female with normal biological parents
HAPLOTYPE		None
FOUND IN COMBINATION WITH ABNORMAL HB(S)		None
FOUND IN COMBINATION WITH BETA-THAL ALLELE(S)		None
OTHER INFORMATION		Father and mother were 45 and 44 years old, respectively, at time of birth. Analyses of blood and serum types, isozymes, HLA markers, and polymorphisms in the beta-globin cistron exclude non-paternity (<1/10,000). The thalassemia mutation is on the paternal chromosome and is considered to have occurred spontaneously, perhaps because of the advanced paternal age

REFERENCES
1.		Tonz, O., Winterhalter, K.H., and Glatthaar, B.E.: Nature New Biol., 241:127, 1973.
2.		Chehab, F.F., Winterhalter, K.H., and Kan, Y.W.: Blood, 74:852, 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.