MUTATION IVS-I (-3) or codon 29 (C->T); GGC(Gly)->GGT(Gly)
 
AMINO ACID REPLACEMENT None
TYPE OF BETA-THAL beta+
MECHANISM 
 29 30  IVS-I               
GGC·AG·GTTGGT->GGT·AG·GTTGGT
      ^         ^     ^
The C->T change occurs 2 nucleotides 5' to the GT donor splice site and creates a new splice site causing a premature termination at the new codon 59 (TGA = stop codon)
IDENTIFICATION Cloning of the beta-globin gene; sequencing
HEMATOLOGY IN HETEROZYGOTE(S) None reported
HEMATOLOGY IN HOMOZYGOTE(S) None reported
OCCURRENCE In a few Lebanese patients
HAPLOTYPE II [- O + + - + + +]
FOUND IN COMBINATION WITH ABNORMAL HB(S) None reported
FOUND IN COMBINATION WITH BETA-THAL ALLELE(S) None reported
OTHER INFORMATION Some normal splicing of the mRNA remains resulting in a beta+-thal
       
REFERENCES
1. Chehab, F.F., Der Kaloustian, V., Khouri, F.P, Deeb, S.S., and Kan, Y.W.: Blood, 69:1141, 1987.

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.