MUTATION		Codon 35 (C->A); TAC->TAA (Tyr->Term codon)
AMINO ACID REPLACEMENT		None
TYPE OF BETA-THAL		beta°
MECHANISM		The C->A mutation changes the codon 35 (Tyr) to a nonsense codon terminating translation
IDENTIFICATION		Amplification of the beta-globin gene; sequencing of amplified DNA; cloning of the beta gene and sequencing; hybridization with mutation specific probes
HEMATOLOGY IN HETEROZYGOTE(S)		The mother of the proband; hematology is typical of a beta°-thal
HEMATOLOGY IN HOMOZYGOTE(S)		Not observed
OCCURRENCE		In a few Thai families
HAPLOTYPE		[+ O - - - - - +]
FOUND IN COMBINATION WITH ABNORMAL HB(S)		Not observed
FOUND IN COMBINATION WITH BETA-THAL ALLELE(S)		The proband had Hb E-beta-thal: Hb 7.8 g/dl; MCV 70 fl; MCH 22 pg; Hb F 47.7%
OTHER INFORMATION		None

REFERENCES
1.		Fucharoen, S., Fucharoen, G., Fucharoen, P., and Fukumaki, Y.: J. Biol. Chem., 264:7780, 1989.
2.		Thein, S.L., Winichagoon, P., Hesketh, C., Best, S., Fucharoen, S., Wasi, P., and Weatherall, D.J.: Am. J. Hum. Genet., 47:369, 1990.

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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.