MUTATION IVS-I-110 (G->A)
 
AMINO ACID REPLACEMENT None
TYPE OF BETA-THAL beta+; the mutation is 21 nucleotides 5' to the acceptor splice site AG^GC
MECHANISM Formation of a new splice site (see scheme) resulting in an 80% abnormal spliced mRNA and 20% normal mRNA 
Codon #                                    30  31  32  33  
                                            g Leu Leu Val  
Normal      ctattggt cta ttt tcc cac cct tagG·CTG·CTG·GTG·G
                                            ^              
                   g Leu Phe Ser His Pro Term              
Beta-Thal   ctattagT·CTA·TTT·TCC·CAC·CCT·TAGG·CTG·CTG·GTG·G
                   ^                        ^
IDENTIFICATION Cloning of the beta-globin gene; amplification of the beta-globin gene; sequencing; identification with allele specific probes
HEMATOLOGY IN HETEROZYGOTE(S) From Ref. 3 (n=75): Hb 11.85±1.8 g/dl; MCV 69.5±6.9 fl; MCH 20.9±2.0 fl; Hb A2 4.65±0.5%; Hb F 1.2±1.15%
HEMATOLOGY IN HOMOZYGOTE(S) Almost invariably transfusion-dependent beta-thal major
OCCURRENCE One of the most common beta-thal alleles in Mediterranean countries; see Tables III, IV, V, VI, VII, VIII, IX, and X
HAPLOTYPE Haplotype I
FOUND IN COMBINATION WITH ABNORMAL HB(S) Hb S; Hb C; Hb E; Hb Knossos, etc.
FOUND IN COMBINATION WITH BETA-THAL ALLELE(S) Many
OTHER INFORMATION
       
REFERENCES
1. Spritz, R.A., Jagadeeswaran, P., Choudary, P.V., Biro, P.A., Elder, J.T., deRiel, J.K., Manley, J.L., Gefter, M.L., Forget, B.G., and Weissman, S.M.: Proc. Natl. Acad. Sci. USA, 78:2455, 1981.
2. Westaway, D. and Williamson, R.: Nucleic Acids Res., 9:1777, 1981.
3. 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.
4. Baysal, E., Indrak, K., Bozkurt, G., Berkalp, A., Aritkan, E., Old, J.M., Ioannou, P., Angastiniotis, M., Droushiotou, A., Yuregir, G.T., Kilinç, Y., and Huisman, T.H.J.: Br. J. Haematol., 81:607, 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.