MUTATION 3.7 kb (type I) deletion involving the 3' part of the alpha2 gene and 5' part of the alpha1 gene
TYPE OF ALPHA-THAL alpha-Thal-2 [-alpha/]
IDENTIFICATION Gene mapping; PCR methodology with probes 5' and 3' to the deletion
HEMATOLOGY IN HETEROZYGOTE(S) Hb 12.5-15.0 g/dl; MCV 78-88 fl; MCH 25-28 pg; Hb A2 1.8-2.8%; Hb F <1%
HEMATOLOGY IN HOMOZYGOTE(S) Hb 11-13 g/dl; MCV 65-70 fl; MCH 20-23 pg; Hb A2 1.8-2.5%; Hb F <1%
OCCURRENCE The 3.7 kb deletion is the most common TYPE OF ALPHA-THAL-2 found in numerous populations often at extremely high frequencies (India, Far Eastern countries; African populations, Mediterranean populations, etc.)
HAPLOTYPE Not determined
FOUND IN COMBINATION Hb S, Hb C, and many other beta chain variants
FOUND IN COMBINATION With numerous deletional and nondeletional alpha-thal determinants
1. Embury, S.H., Miller, J.A., Dozy, A.M., Kan, Y.W., Chan, V., and Todd, D.: J. Clin. Invest., 66:1319, 1980.
2. Kazazian, H.H., Jr.: Semin. Hematol., 27:209, 1990.
3. Higgs, D.R.: in The Haemoglobinopathies, edited by D.R. Higgs and D.J. Weatherall, Bailliere's Clinical Haematology, Vol. 6, page 117, W.B. Saunders Company, London, 1993.
4. Baysal, E. and Huisman, T.H.J.: Am. J. Hematol., 46:208, 1994.

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.