C-Harlem.html

Hb C-Harlem	beta6(A3)Glu->Val;
	beta73(E17)Asp->Asn


HEMATOLOGY		Normal in the heterozygote
ELECTROPHORESIS		Hb X moves like Hb C in standard electrophoresis at alkaline pH; at acidic pH (agar gel) Hb X occupies the position of Hb S
CHROMATOGRAPHY		Hb X elutes with Hb A₂ in anion exchange chromatography; Hb X also separates from Hb A on a CM-Sephadex column
STRUCTURE STUDIES		Tryptic digestion of AE-beta^X chain; separation of peptides by fingerprinting; amino acid analysis; sequencing
DNA ANALYSES		Not reported; presumed mutations GAG->GTG and GAT->AAT at codons 6 and 73
FUNCTION STUDIES		Normal
STABILITY		Hb X is less stable than Hb A and Hb S
OCCURRENCE		Found in several (10-15) Black families
OTHER INFORMATION		Quantity in the heterozygote 40-44%; sickling when deoxygenated; when found together with Hb S the condition resembles sickle cell anemia; insoluble in concentrated phosphate; gels at higher concentrations than Hb S; the beta73 Asp->Asn replacement is characteristic for Hb Korle- Bu


REFERENCES
1.		Bookchin, R.M., Nagel, R.L., and Ranney, H.M.: J. Biol. Chem., 242:248, 1967.
2.		Nagel, R.L. and Bookchin, R.M.: Nature, 241:143, 1973.
3.		Moo-Penn, W.F., Bechtel, K., Jue, D., Chan, M.S., Hopkins, G., Schneider, N.J., Wright, J., and Schmidt, R.M.: Blood, 46:363, 1975.

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.