Hb Quebec-Chori	beta87(F3)Thr->Ile

CONTACT		External
HEMATOLOGY		Not reported; presumably normal in the heterozygote
ELECTROPHORESIS		No separations at alkaline pH and by IEF
CHROMATOGRAPHY		The betaX, betaA, and betaS chains readily separate by reversed phase HPLC (betaX elutes between betaA and alpha)
STRUCTURE STUDIES		Tryptic digestion of AE-globin X; separation of peptides by reversed phase HPLC; amino acid analysis; sequencing by liquid secondary ion mass spectrometry
DNA ANALYSES		Not reported; presumed mutation ACA->ATA at codon 87
FUNCTION STUDIES		Normal
STABILITY		Not reported
OCCURRENCE		Found in a 3-year-old girl and her mother (of English-Irish-French-Canadian extraction); the father was from Ghana
OTHER INFORMATION		Occurred in association with Hb S; this compound heterozygote has a mild to moderately severe sickle cell disease; quantity in the heterozygote not reported but appears to be ~40% by reversed phase HPLC; quantities of Hb X and Hb S in the compound heterozygote estimated at 60% (Hb X) and 40% (Hb S); the beta87(F3) amino acid is important as an interaction site with beta6(A3) (Glu->Val in Hb S) in polymerization upon deoxygenation; the introduction of isoleucine increases this interaction

REFERENCES
1.		Witkowska, H.E., Lubin, B.H., Beuzard, Y., Baruchel, S., Esseltine, D.W., Vichinsky, E.P., Kleman, K.M., Bardakdjian-Michau, J., Pinkoski, L., Cahn, S., Roitman, E., Green, B.N., Falick, A.M., and Shackleton, C.H.L.: N. Engl. J. Med., 325:1150, 1991.

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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.