Homozygous SYNE1 mutation causes congenital onset of muscular weakness with distal arthrogryposis: a genotype-phenotype correlation.

Authors:
Matthias Baumann, Elisabeth Steichen-Gersdorf, Birgit Krabichler, Britt-Sabina Petersen, Ulrike Weber, Wolfgang M Schmidt, Johannes Zschocke, Thomas Müller, Reginald E Bittner, Andreas R Janecke
Year of publication:
2016
Volume:
-
Issue:
-
Issn:
1018-4813
Journal title abbreviated:
EUR J HUM GENET
Journal title long:
European journal of human genetics
Impact factor:
5.351
Abstract:
The exceptionally large SYNE1 (spectrin repeat-containing nuclear envelope protein 1) gene encodes different nesprin-1 isoforms, which are differentially expressed in striated muscle and in cerebellar and cerebral neurons. Nesprin-1 isoforms can function in cytoskeletal, nuclear, and vesicle anchoring. SYNE1 variants have been associated with a spectrum of neurological and neuromuscular disease. Homozygosity mapping combined with exome sequencing identified a disease-causing nonsense mutation in the ultimate exon of full-length SYNE1 transcript in an 8-year-old boy with distal arthrogryposis and muscular hypotonia. mRNA analysis showed that the mutant transcript is expressed at wild-type levels. The variant truncates nesprin-1 isoforms for the C-terminal KASH (Klarsicht-ANC-Syne homology) domain. This is the third family with recessive arthrogryposis caused by homozygous distal-truncating SYNE1 variants. There is a SYNE1 genotype-phenotype correlation emerging, with more proximal homozygous SYNE1 variants causing recessive cerebellar ataxia of variable onset (SCAR8; ARCA-1).European Journal of Human Genetics advance online publication, 26 October 2016; doi:10.1038/ejhg.2016.144.