Hb La Roche-sur-Yon beta81(EF5)Leu->His
(beta80 Asn is partially deaminated)
CONTACT 2,3-DPG pocket
HEMATOLOGY Normal in the heterozygote
ELECTROPHORESIS The presence of two abnormal Hb components were observed by IEF; one (15%) displayed a pI slightly above that of Hb A; the second (12%) focused with a lower pI than Hb F; globin chain electrophoresis in 6 M urea at pH 6.0 showed two abnormal beta chains and only one at pH 9.0
CHROMATOGRAPHY Not reported; the betaX and betaA chains can be separated by reversed phase HPLC
STRUCTURE STUDIES Tryptic digestion of AE-betaX chain; peptides were separated by reversed phase HPLC; amino acid analysis; sequencing
DNA ANALYSES Not reported; presumed mutation CTC->CAC at codon 81
FUNCTION STUDIES Slightly increased oxygen affinity
OCCURRENCE Found in an 18-year-old female of Portuguese origin; appears to have arisen as a de novo mutation
OTHER INFORMATION About 50% of the variant has the asparagine residue at position 80 deaminated
1. Wajcman, H., Kister, J., Vasseur, C., Blouquit, Y., Trastour, J.C., Cottenceau, D., and Galacteros, F.; Biochim. Biophys. Acta, 1138:127, 1992.

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.