TYPE Anglo-Saxon (epsilongammadeltabeta)°-Thal (see Fig. 17)
 
CAUSE This condition is caused by a large deletion of 95.9 kb that removes DNA starting ~50 kb upstream from the epsilon gene to the second exon of the beta gene.
DETECTION Gene mapping with different enzymes and several probes.
PHENOTYPE This form of thalassemia is characterized by the absence of production of gamma-, delta-, and beta-globins. The proband had the following hematology: Hb 10.4 g/dl; PCV 0.32 l/l; RBC 3.81 x 1012/l; MCV 84 fl; MCH 27 pg; MCHC 32 g/dl; Hb F 52%; Hb A2 1.2%. At 1 year of age, the patient had no anemia but her red cells were hypochromic and microcytic. Hb A2 was 2.7% and Hb F 3.1%. The proband's father was of English origin and the mother of German descent. The father had the same abnormality; he was not anemic and only slightly hypochromic and microcytic. Similar features were found in seven other family members.
DISTRIBUTION Found in one Anglo-Saxon family.
       
REFERENCES
1. Kan, Y.W., Forget, B.G., and Nathan, D.G.: N. Engl. J. Med., 286:129, 1972.
2. Orkin, S.H., Goff, S.C., and Nathan, D.G.: J. Clin. Invest., 67:878, 1981.


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.