MUTATION Codon 112 (T->A); TGT(Cys)->TGA(stop codon)
 
AMINO ACID REPLACEMENT None
TYPE OF BETA-THAL beta°
MECHANISM This mutation results in a terminating codon (codon 112) and the synthesis of a shortened betaX chain (111 amino acids) which likely is rapidly catabolized
IDENTIFICATION Amplification of the beta-globin gene; DNA sequencing; dot-blot analysis with mutation specific probes
HEMATOLOGY IN HETEROZYGOTE(S) Mother and daughter (see table)
Sex-Age Hb
g/dl
MCV
fl
MCH
pg
A2
%
F
%
Ggamma
%
F-46 10.6 65.1 23.6 3.7 <1.0 79.9
F-18 10.5 60.1 19.6 4.6 <1.0 77.7

HEMATOLOGY IN HOMOZYGOTE(S) Not observed
OCCURRENCE In a Slovakian family
HAPLOTYPE Not reported
FOUND IN COMBINATION WITH ABNORMAL HB(S) None
FOUND IN COMBINATION WITH BETA-THAL ALLELE(S) None
OTHER INFORMATION No Heinz bodies or inclusion bodies after incubation with dye were detected and no abnormal betaX chain was found; there is no dominant TYPE OF BETA-THAL with chronic hemolytic anemia
       
REFERENCES
1. Divoky, V., Gu, L-H., Indrak, K., Mocikova, K., Zarnovicanova, M., and Huisman, T.H.J.: Br. J. Haematol., 83:523, 1993.


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.