Copy number variation of LINGO1 in familial dystonic tremor

Neurol Genet. 2019 Feb 4;5(1):e307. doi: 10.1212/NXG.0000000000000307. eCollection 2019 Feb.

Abstract

Objective: To elucidate the genetic cause of a large 5 generation South Indian family with multiple individuals with predominantly an upper limb postural tremor and posturing in keeping with another form of tremor, namely, dystonic tremor.

Methods: Whole-genome single nucleotide polymorphism (SNP) microarray analysis was undertaken to look for copy number variants in the affected individuals.

Results: Whole-genome SNP microarray studies identified a tandem duplicated genomic segment of chromosome 15q24 present in all affected family members. Whole-genome sequencing demonstrated that it comprised a ∼550-kb tandem duplication encompassing the entire LINGO1 gene.

Conclusions: The identification of a genomic duplication as the likely molecular cause of this condition, resulting in an additional LINGO1 gene copy in affected cases, adds further support for a causal role of this gene in tremor disorders and implicates increased expression levels of LINGO1 as a potential pathogenic mechanism.