To the top

Page Manager: Webmaster
Last update: 9/11/2012 3:13 PM

Tell a friend about this page
Print version

New morphologic and genet… - University of Gothenburg, Sweden Till startsida
To content Read more about how we use cookies on

New morphologic and genetic findings in cap disease associated with beta-tropomyosin (TPM2) mutations.

Journal article
Authors Monica Ohlsson
S Quijano-Roy
Niklas Darin
G Brochier
E Lacène
D Avila-Smirnow
M Fardeau
Anders Oldfors
Homa Tajsharghi
Published in Neurology
Volume 71
Issue 23
Pages 1896-901
ISSN 1526-632X
Publication year 2008
Published at
Pages 1896-901
Language en
Subject categories Cell and Molecular Biology


OBJECTIVE: Mutations in the beta-tropomyosin gene (TPM2) are a rare cause of congenital myopathies with features of nemaline myopathy and cap disease and may also cause distal arthrogryposis syndromes without major muscle pathology. We describe the muscle biopsy findings in three patients with cap disease and novel heterozygous mutations in TPM2. METHODS: Three unrelated patients with congenital myopathy were investigated by muscle biopsy and genetic analysis. RESULTS: All three patients had early-onset muscle weakness of variable severity and distribution. Muscle biopsy demonstrated in all three patients near uniformity of type 1 fibers and an unusual irregular and coarse-meshed intermyofibrillar network. By electron microscopy, the myofibrils were broad and partly split, and the Z lines appeared jagged. In one of the patients caps structures were identified only by electron microscopy, and in one patient they were identified only in a second biopsy at adulthood. Three novel, de novo, heterozygous mutations in TPM2 were identified: a three-base pair deletion in-frame (p.Lys49del), a three-base pair duplication in-frame (p.Gly52dup), and a missense mutation (p.Asn202Lys). CONCLUSIONS: Mutations in TPM2 seem to be a frequent cause of cap disease. Because cap structures may be sparse, other prominent features, such as a coarse-meshed intermyofibrillar network and jagged Z lines, may be clues to correct diagnosis and also indicate that the pathogenesis involves defective assembly of myofilaments.

Page Manager: Webmaster|Last update: 9/11/2012

The University of Gothenburg uses cookies to provide you with the best possible user experience. By continuing on this website, you approve of our use of cookies.  What are cookies?