MUTATION		Codon 126 (-T); GTG(Val)->G-G
AMINO ACID REPLACEMENT		None (Hb Vercelli)
TYPE OF BETA-THAL		beta°
MECHANISM		This frameshift results in a stop codon at codon 157 and the formation of a betaX chain which is 156 amino acids long; this chain is rapidly catabolized resulting in a beta-thal condition
IDENTIFICATION		Amplification of the beta-globin gene; DNA sequencing; dot-blot analysis with allele specific probes
HEMATOLOGY IN HETEROZYGOTE(S)		Mild anemia (Hb 9.0 g/dl); slightly elevated Hb A2 (3.5%); elevated Hb F (10.8%); limited inclusion bodies after incubation with dye; the parents are normal
HEMATOLOGY IN HOMOZYGOTE(S)		None
OCCURRENCE		In a North Italian female
HAPLOTYPE		Not determined
FOUND IN COMBINATION WITH ABNORMAL HB(S)		None
FOUND IN COMBINATION WITH BETA-THAL ALLELE(S)		None
OTHER INFORMATION		No abnormal Hb was detected by electrophoresis and no betaX chain by chromatography. Stability tests were normal

REFERENCES
1.		Murru, S., Loudianos, G., Deiana, M., Camaschella, C., Sciarratta, G.V., Agosti, S., Parodi, M.I., Cerruti, P., Cao, A., and Pirastu, M.: Blood, 77:1342, 1991.

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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.