Novel mutation in optineurin causing aggressive ALS+/−frontotemporal dementia

Novel mutation in optineurin causing aggressive ALS+/−frontotemporal dementia:

Abstract

Objective

Mutations in optineurin (OPTN) have been identified in familial and sporadic amyotrophic lateral sclerosis (ALS). We screened a cohort of Chinese patients for mutations in optineurin. We also performed an extensive literatures review of all mutations in optineurin identified previously to detect genotype–phenotype associations.

Methods

All 16 exons of the OPTN gene in a cohort of 15 familial ALS indexes and 275 sporadic ALS patients of Chinese origin were sequenced by targeted next generation sequencing.

Results

Two known heterozygous missense mutations in the OPTN, c.1481T> G (p.L494W), and c.1546G> C (p.E516Q), as well as one novel heterozygous missense mutation c.1690G> C (p.D564H) were each detected in one sporadic ALS patient. The patient carrying the p.E516Q mutation developed clinical features of ALS‐frontotemporal dementia (FTD) and the patient carrying the p.D564H mutation showed a phenotype of ALS. They both had an aggressive course, with a survival of 18 and 14 months respectively. Literature review showed that the clinical phenotypes in OPTN mutated ALS were not homogeneous, although some individuals showed a relatively slow progression and a long duration, some mutations carriers developed an aggressive progression and a short survival.

Interpretation

OPTN mutations contribute to ALS in Chinese population and account for 0.8% of sporadic ALS patients and 1.5% of familial ALS in the pooled Chinese ALS cohorts. Mutations in optineurin can cause aggressive ALS+/−FTD.