Hb Yokohama	beta31(B13)Leu->Pro

CONTACT		Heme contact; internal residue
HEMATOLOGY		Severe hemolytic anemia in the heterozygote; Heinz bodies
ELECTROPHORESIS		Hb X and Hb A do not separate at alkaline pH; no separation by IEF
CHROMATOGRAPHY		No separation obtained; the betaX chain elutes ahead of the betaA chain in the reversed phase HPL chromatogram
STRUCTURE STUDIES		The betaX chain was isolated by pCMB precipitation; proteolytic digestion; separation of peptides by reversed phase HPLC; fingerprinting; amino acid analysis; sequencing
DNA ANALYSES		A CTG->CCG mutation at codon 31 (Ref. 2)
FUNCTION STUDIES		Slightly decreased oxygen affinity
STABILITY		Unstable
OCCURRENCE		Found in members of a Japanese family and in a Serbian teenager
OTHER INFORMATION		Quantity in heterozygotes not definitely determined; a de novo mutation

REFERENCES
1.		Nakatsuji, T., Miwa, S., Ohba, Y., Hattori, Y., Miyaji, T., Hino, S., and Matsumoto, N.: Hemoglobin, 5:667, 1981.
2.		Plaseska, D., Jankovic, L., Dimovski, A.J., Milenovic, D., Juricic, D., and Efremov, G.D.: Hemoglobin, 15:469, 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.