-.-(MED-II),.a.deletion.of.26.5.kb.invol.html

MUTATION

- -(MED-II); a deletion of 26.5 kb involving the two alpha and the zeta genes (see Fig. 24)

AMINO ACID REPLACEMENT

None

TYPE OF ALPHA-THAL

alpha-Thal-1 [- -/]

MECHANISM

Deletion of the three functional genes results in a complete absence of alpha- and zeta-mRNAs

IDENTIFICATION

Gene mapping; see scheme below

A comparison of five types of alpha-thal-1 (from Ref. 1).

[Figure not yet available on-line.]

HEMATOLOGY IN HETEROZYGOTE(S)

Not reported

HEMATOLOGY IN HOMOZYGOTE(S)

None

OCCURRENCE

In a few Turkish families and in other Mediterranean populations

HAPLOTYPE

Not determined

FOUND IN COMBINATION WITH ABNORMAL HB(S)

Not reported

FOUND IN COMBINATION

With the -alpha(3.7 kb) deletion causing Hb H disease: Hb 10.4-12.3 g/dl; MCV 57-68 fl; MCH 16.5-18.2 pg; Hb A₂ 0.6-1.1%; Hb H 6-11%

OTHER INFORMATION

None


REFERENCES
1.		Kutlar, F., Gonzalez-Redondo, J.M., Kutlar, A., Gurgey, A., Altay, Ç., Efremov, G.D., Kleman, K., and Huisman, T.H.J.: Hum. Genet., 82:179, 1989.

This material is from the book A Syllabus of Thalassemia Mutations (1997) by Titus H.J. Huisman, Marianne F.H. Carver, and Erol Baysal, published by The Sickle Cell Anemia Foundation in Augusta, GA, USA. Copyright © 1997 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 permission in writing from the Author.