MUTATION Codon 39 (C->T); CAG(Gln)->TAG(stop codon)
MECHANISM This mutation changes codon 39 into a stop codon terminating translation
IDENTIFICATION Cloning of the beta-globin gene; amplification of the beta-globin gene and sequencing; dot-blot analysis; ARMS; gene mapping with MaeI
HEMATOLOGY IN HETEROZYGOTE(S) Typical for beta°-thal with low MCV and MCH values; microcytosis; hypochromia (n=10): Hb 11.1±1.35 g/dl; MCV 72.6±8.5 fl; MCH 20.2±1.1 pg; Hb A2 4.85±0.5%; Hb F 1.25±1.0% (Ref. 4)
HEMATOLOGY IN HOMOZYGOTE(S) Severe transfusion-dependent beta-thal
OCCURRENCE One of the major beta-thal alleles in the Mediterranean area; see Tables III through X for frequency data
FOUND IN COMBINATION WITH ABNORMAL HB(S) With Hb S, Hb C, Hb E, causing moderately severe thalassemia intermedia (and sickling)
FOUND IN COMBINATION WITH BETA-THAL ALLELE(S) With numerous beta° or beta+ alleles; in most instances, the compound heterozygotes are transfusion-dependent
OTHER INFORMATION The beta°-thal codon 39 mutation can also be detected by enzymatic digestion with MaeI (Ref. 3)
1. Orkin, S.H. and Goff, S.C.: J. Biol. Chem., 256:9782, 1981.
2. Trecartin, R.F., Liebhaber, S.A., Chang, J.C., Lee, K.Y., and Kan, Y.W.: J. Clin. Invest., 68:1012, 1981.
3. Thein, S.L., Wainscoat, J.S., Lynch, J.R., Weatherall, D.J., Sampietro, M., and Fiorelli, G.: The Lancet, i:1095, 1985.
4. Öner, R., Altay, Ç., Gurgey, A., Aksoy, M., Kilinç, Y., Stoming, T.A., Reese, A.L., Kutlar, A., Kutlar, F., and Huisman, T.H.J.: Hemoglobin, 14:1, 1990.

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.