MUTATION Codons 74/75 (-C); GGC·CTG(Gly·Leu)->GG-·CTG
 
AMINO ACID REPLACEMENT None
TYPE OF BETA-THAL beta°
MECHANISM The loss of a C creates a change in the reading frame resulting in a premature termination of translation because of a stop codon at codon 88 (TGA)
IDENTIFICATION Amplification of DNA; sequencing
HEMATOLOGY IN HETEROZYGOTE(S) Both parents have the codons 74/75 (-C) heterozygosity; mild anemia with microcytosis and hypochromia; Hb A2 5.1-5.8%; MCV 65-68 fl
HEMATOLOGY IN HOMOZYGOTE(S) Severe anemia; transfusion dependency
OCCURRENCE In a 6-year-old Turkish boy; he is a homozygote
HAPLOTYPE Not reported
FOUND IN COMBINATION WITH ABNORMAL HB(S) None
FOUND IN COMBINATION WITH BETA-THAL ALLELE(S) None
OTHER INFORMATION Patient was splenectomized at the age of 5 years
       
REFERENCES
1. Basak, A.N., Özer, A., Özçelik, ., Kirdar, B., and Gürgey, A.: Hemoglobin, 16:309, 1992.


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.