MUTATION G->A at codon 104 of the alpha2 gene; TGC->TAC
 
AMINO ACID REPLACEMENT Cys->Tyr (Hb Sallanches)
TYPE OF ALPHA-THAL alpha-Thal-2 [alpha(T)alpha/alphaalpha]
MECHANISM The alpha-Sallanches chain, when combined with normal beta, forms an unstable dimer
IDENTIFICATION Amplification; cloning; sequencing; mRNA analysis by RT-PCR
HEMATOLOGY IN HETEROZYGOTE(S) Father and mother are heterozygous: Hb 13.8-14.0 g/dl; MCV 77-79 fl; MCH 24.0-25.5 pg; Hb A2 normal
HEMATOLOGY IN HOMOZYGOTE(S) Homozygous child (3 years old): Hb 8.5 g/dl; MCV 91 fl; MCH 26 pg; Hb A2 <1.0%; Hb H ~5.0%; splenomegaly; reticulocytosis; hemolytic episodes
OCCURRENCE In a French family
HAPLOTYPE Not determined
FOUND IN COMBINATION WITH ABNORMAL HB(S) Not reported
FOUND IN COMBINATION WITH BETA-THAL ALLELE(S) Not reported
OTHER INFORMATION Protein can be detected in small quantities by IEF and HPLC
       
REFERENCES
1. Morlé, F., Francina, A., Ducrocq, R., Wajcman, H., Gonnet, C., Philippe. N., Souillet, G., and Godet, J.: Br. J. Haematol., 91:608, 1995.


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.