Fulltext:
152955.pdf
Embargo:
until further notice
Size:
867.5Kb
Format:
PDF
Description:
Publisher’s version
Publication year
2015Source
Human Genetics, 134, 10, (2015), pp. 1089-97ISSN
Publication type
Article / Letter to editor
Display more detailsDisplay less details
Organization
Human Genetics
Paediatrics - OUD tm 2017
Journal title
Human Genetics
Volume
vol. 134
Issue
iss. 10
Page start
p. 1089
Page end
p. 97
Subject
Radboudumc 0: Other Research RIMLS: Radboud Institute for Molecular Life Sciences; Radboudumc 6: Metabolic Disorders RIMLS: Radboud Institute for Molecular Life Sciences; Radboudumc 7: Neurodevelopmental disorders DCMN: Donders Center for Medical Neuroscience; Radboudumc 9: Rare cancers RIHS: Radboud Institute for Health SciencesAbstract
KCNH1 mutations have recently been described in six individuals with Temple-Baraitser syndrome (TMBTS) and six individuals with Zimmermann-Laband syndrome (ZLS). TMBTS is characterized by intellectual disability (ID), epilepsy, dysmorphic facial features, broad thumbs and great toes with absent/hypoplastic nails. ZLS is characterized by facial dysmorphism including coarsening of the face and a large nose, gingival enlargement, ID, hypoplasia of terminal phalanges and nails and hypertrichosis. In this study, we present four additional unrelated individuals with de novo KCNH1 mutations from ID cohorts. We report on a novel recurrent pathogenic KCNH1 variant in three individuals and add a fourth individual with a previously TMBTS-associated KCNH1 variant. Neither TMBTS nor ZLS was suspected clinically. KCNH1 encodes a voltage-gated potassium channel, which is not only highly expressed in the central nervous system, but also seems to play an important role during development. Clinical evaluation of our mutation-positive individuals revealed that one of the main characteristics of TMBTS/ZLS, namely the pronounced nail hypoplasia of the great toes and thumbs, can be mild and develop over time. Clinical comparison of all published KCNH1 mutation-positive individuals revealed a similar facial but variable limb phenotype. KCNH1 mutation-positive individuals present with severe ID, neonatal hypotonia, hypertelorism, broad nasal tip, wide mouth, nail a/hypoplasia, a proximal implanted and long thumb and long great toes. In summary, we show that the phenotypic variability of individuals with KCNH1 mutations is more pronounced than previously expected, and we discuss whether KCNH1 mutations allow for "lumping" or for "splitting" of TMBTS and ZLS.
This item appears in the following Collection(s)
- Academic publications [246764]
- Electronic publications [134205]
- Faculty of Medical Sciences [93461]
Upload full text
Use your RU credentials (u/z-number and password) to log in with SURFconext to upload a file for processing by the repository team.