MUTATION		Codons 30/31 (GAG·AGG->GAG·- -G) on an alpha-thal-2 globin gene [-alpha(T)]
AMINO ACID REPLACEMENT		None
TYPE OF ALPHA-THAL		alpha-Thal-1 [-alpha(T)/alphaalpha]
MECHANISM		The deletion of 2 nts results in a reading frameshift with a stop codon at codon 55 (TAA)
IDENTIFICATION		Molecular cloning; sequencing; gene mapping
HEMATOLOGY IN HETEROZYGOTE(S)		Similar to most alpha-thal-1 heterozygotes; microcytosis; hypochromia
HEMATOLOGY IN HOMOZYGOTE(S)		Not reported
OCCURRENCE		In a Black family
HAPLOTYPE		Not determined
FOUND IN COMBINATION		With a Hb G-Philadelphia heterozygote [-alpha(G)/-alpha(T)] who produces only alpha(G) chains, no alpha(A) chains, and Hb H; patient has the typical phenotype of Hb H disease
FOUND IN COMBINATION WITH BETA-THAL ALLELE(S)		Not reported
OTHER INFORMATION		The mother has Hb H disease [-alpha(G)/-alpha(T)]; the son alpha-thal trait [-alpha(T)/alphaalpha]; the daughter and grandmother Hb G-Philadelphia trait [-alpha(G)/alphaalpha]

REFERENCES
1.		Rieder, R.F., Woodbury, D.H., and Rucknagel, D.L.: Br. J. Haematol., 32:159, 1976.
2.		Sancar, G.B., Tatsis, B., Cedeno, M.M., and Rieder, R.F.: Proc. Natl. Acad. Sci. USA, 77:6874, 1980.
3.		Safaya, S. and Rieder, R.F.: J. Biol. Chem., 263:4328, 1988.

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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.