Hb Catonsville	Glu- inserted between
	alpha37(C2)Pro and alpha38(C3)Thr

HEMATOLOGY		Mild erythrocytosis; reticulocytosis; hemolytic episodes
ELECTROPHORESIS		Hb X moves faster than Hb A at alkaline pH; at acidic pH Hb X moves between Hb A and Hb F
CHROMATOGRAPHY		Hb X elutes faster than Hb A from a cation exchange HPLC column; no resolution of chains (alphaX and alphaA) by reversed phase HPLC
STRUCTURE STUDIES		Tryptic digestion of alphaX chain; separation of peptides by reversed phase HPLC; amino acid analysis; sequencing
DNA ANALYSES		Insertion of GAA between CCC [codon 37 (= Pro)] and ACC [codon 38 (= Thr)]
FUNCTION STUDIES		Increased oxygen affinity; reduced cooperativity and Bohr effect
STABILITY		Unstable
OCCURRENCE		Found in a young child and his father
OTHER INFORMATION		Quantity in the heterozygote 24.2%

REFERENCES
1.		Moo-Penn, W.F., Swan, D.C., Hine, T.K., Baine, R.M., Jue, D.L., Benson, J.M., Johnson, M.H., Virshup, D.M., and Zinkham, W.H.: J. Biol. Chem., 264:21454, 1989.

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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.