Hb Tacoma	beta30(B12)Arg->Ser

CONTACT		alpha1beta1 contact
HEMATOLOGY		Normal in the heterozygote; Heinz bodies
ELECTROPHORESIS		Hb X and Hb A separate at alkaline pH; Hb X is slightly faster than Hb A; best separation is obtained by IEF
CHROMATOGRAPHY		Separation of Hb X and Hb A by anion exchange chromatography and by cation exchange HPLC
STRUCTURE STUDIES		Proteolytic digestion of betaX+betaA chains; reversed phase HPLC or cation exchange chromatography; amino acid analysis
DNA ANALYSES		An AGG->AGT mutation at codon 30 (Ref. 3); codon 30 is divided by intron 1 as follows: ---CTT*AG<-IVS-I->G*CTG*CTG---. It is the first nt G of exon 2 that is changed to T
FUNCTION STUDIES		Normal oxygen affinity; decreased Bohr effect and cooperativity
STABILITY		Unstable
OCCURRENCE		Found in a few North European families (Russia, Finland, Sweden, USA)
OTHER INFORMATION		Quantity in heterozygotes 43%

REFERENCES
1.		Baur, E.W. and Motulsky, A.G.: Humangenetik, 1:621, 1965.
2.		Brimhall, B., Jones, R.T., Baur, E.W., and Motulsky, A.G.: Biochemistry, 8:2125, 1969.
3.		Landin, B. and Jeppsson, J-O.: Hemoglobin, 17:303, 1993.

---

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.