Hb Icaria alpha142, Term->Lys (TAA->AAA in alpha2);
modified C-terminal sequence is the same
as Hb CS except that residue 142 is LYS
HEMATOLOGY Normal in the heterozygote
ELECTROPHORESIS Hb X moves slower than Hb A2 at alkaline pH
CHROMATOGRAPHY Hb X was isolated on an Amberlite IRC-50 column
STRUCTURE STUDIES Tryptic digestion of alphaX chain; separation of peptides by fin-gerprinting; amino acid analysis; sequencing
DNA ANALYSES A TAA->AAA mutation at codon alpha142 (alpha2); the Hb Icaria abnormality can best be identified by sequencing of the alpha2 gene or by dot-blot analysis with specific probes
STABILITY Not reported
OCCURRENCE Found in a female living on the island of Icaria in the Aegean Sea, and in a Macedonian family in combination with alpha-thal-1
OTHER INFORMATION Quantity in the heterozygote less than 1%; found in combination with an alpha-thal-1 [the -(alpha)20.5 kb deletion] causing Hb H disease
1. Clegg, J.B., Weatherall, D.J., Contopolou-Griva, I., Caroutsos, K., Poungouras, P., and Tsevrenis, H.: Nature, 251:245, 1974.
2. Efremov, G.D., Josifovska, O., Nikolov, N., Codrington, J.F., Oner, C., Gonzalez-Redondo, J.M., and Huisman, T.H.J.: Br. J. Haematol., 75:250, 1990.

This material is from the book A Syllabus of Human Hemoglobin Variants (1996) by Titus H.J. Huisman, Marianne F.H. Carver, and Georgi D. Efremov, published by The Sickle Cell Anemia Foundation in Augusta, GA, USA. Copyright © 1996 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 written permission.