The Andersen-Tawil syndrome (ATS) is characterized by hypo-normokaliemic muscle periodic paralysis, dysmorphic features and ventricular arrhythmias. Most cases are caused by mutations in KCNJ2, encoding for the potassium inwardly rectifying channel, Kir2.1 (ATS1). Although KCNJ2 mutations show no obvious genotype-phenotype correlations and incomplete penetrance, signs of cardiac involvement are usually present in most ATS1 cases. In contrast, here we describe an Italian ATS1 patient, carrying a c.574A→G mutation in KCNJ2, who had both facial dysmorphisms and muscle periodic paralysis but who did not manifest any cardiac involvement, although the same mutation was originally described in a Japanese kindred, in which all affected individuals manifested a severe cardiac phenotype.

1.
Andersen DE, Krasilnikoff PA, Overvad H: Intermittent muscular weakness, extrasystoles, and multiple developmental anomalies: a new syndrome? Acta Paediatr Scand 1971;60:559–564.
2.
Tawil R, Ptacek LJ, Pavlakis SG, De Vivo DC, Penn AS, Ozsdemir C, Griggs RC: Andersen syndrome: potassium sensitive periodic paralysis, ventricular ectopy, and dysmorphic features. Ann Neurol 1994;35:326–330.
3.
Sansone V, Griggs RC, Meola G, Ptacek LJ, Barohn R, Iannaccone S, Bryan W, Baker N, Janas SJ, Scott W, Ririe D, Tawil R: Andersen’s syndrome: a distinct periodic paralysis. Ann Neurol 1997;42:305–312.
4.
Venance SL, Cannon SC, Fialho D, Fontaine B, Hanna MG, Ptacek LJ, Tristani-Firouzi M, Tawil R, Griggs RC, CINCH investigators: The primary periodic paralyses: diagnosis, pathogenesis and treatment. Brain 2006;129:8–17.
5.
Plaster NM, Tawil R, Tristani-Firouzi M, Canún S, Bendahhou S, Tsunoda A, Donaldson MR, Iannaccone ST, Brunt E, Barohn R, Clark J, Deymeer F, George AL Jr, Fish FA, Hahn A, Nitu A, Ozdemir C, Serdaroglu P, Subramony SH, Wolfe G, Fu YH, Ptácek LJ: Mutations in Kir2.1 cause the developmental and episodic electrical phenotypes of Andersen’s syndrome. Cell 2001;105:511–519.
6.
Donaldson MR, Yoon G, Fu YH, Ptacek LJ: Andersen-Tawil syndrome: a model of clinical variability, pleiotropy, and genetic heterogeneity. Ann Med 2004;(suppl 1): 92–97.
7.
Tristani-Firouzi M, Etheridge SP: Kir 2.1 channelopathies: the Andersen-Tawil syndrome. Pflugers Arch 2010;460:289–294.
8.
Zhang L, Woodrow Benson D, Tristani-Firouzi M, Ptacek LJ, Tawil R, Schwartz PJ, George Al L, Horie M, Andelfinger G, Snow GL, Fu Y-H, Ackerman MJ, Vincent GM: Electrocardiographic features in Andersen-Tawil syndrome patients with KCNJ2 mutations: characteristic T-U-wave patterns predict the KCNJ2 genotype. Circulation 2005;111:2720–2726.
9.
Haruna Y, Kobori A, Makiyama T, Yoshida H, Akao M, Doi T, Tsuji K, Ono S, Nishio Y, Shimizu W, Inoue T, Murakami T, Tsuboi N, Yamanouchi H, Ushinohama H, Nakamura Y, Yoshinaga M, Horigome H, Aizawa Y, Kita T, Horie M: Genotype-phenotype correlations of KCNJ2 mutations in Japanese patients with Andersen-Tawil syndrome. Hum Mutat 2007;28:208.
10.
Yoon G, Oberoi S, Tristani-Firouzi M, Etheridge SP, Quitania L, Kramer JH, Miller BL, Fu YH, Ptacek LJ: Andersen-Tawil syndrome: prospective cohort analysis and expansion of the phenotype. Am J Med Genet 2006;140:312–321.
11.
Davies NP, Imbrici P, Fialho D, Herd C, Bilsland LG, Weber A, Mueller R, Hilton-Jones D, Ealing J, Boothman BR, Giunti P, Parsons LM, Thomas M, Manzur AY, Jurkat-Rott K, Lehmann-Horn F, Chinnery PF, Rose M, Kullmann DM, Hanna MG: Andersen-Tawil syndrome: new potassium channel mutations and possible phenotypic variation. Neurology 2005;65:1083–1089.
12.
Ai T, Fujiwara Y, Tsuji K, Otani H, Nakano S, Kubo Y, Horie M: Novel KCNJ2 mutation in familial periodic paralysis with ventricular dysrhythmia. Circulation 2002;105:2592–2594.
Copyright / Drug Dosage / Disclaimer
Copyright: All rights reserved. No part of this publication may be translated into other languages, reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying, recording, microcopying, or by any information storage and retrieval system, without permission in writing from the publisher.
Drug Dosage: The authors and the publisher have exerted every effort to ensure that drug selection and dosage set forth in this text are in accord with current recommendations and practice at the time of publication. However, in view of ongoing research, changes in government regulations, and the constant flow of information relating to drug therapy and drug reactions, the reader is urged to check the package insert for each drug for any changes in indications and dosage and for added warnings and precautions. This is particularly important when the recommended agent is a new and/or infrequently employed drug.
Disclaimer: The statements, opinions and data contained in this publication are solely those of the individual authors and contributors and not of the publishers and the editor(s). The appearance of advertisements or/and product references in the publication is not a warranty, endorsement, or approval of the products or services advertised or of their effectiveness, quality or safety. The publisher and the editor(s) disclaim responsibility for any injury to persons or property resulting from any ideas, methods, instructions or products referred to in the content or advertisements.
You do not currently have access to this content.