Optineurin mutations in patients with sporadic amyotrophic lateral sclerosis in China.

The purpose of this study was to assess the frequency of optineurin (OPTN) mutation in amyotrophic lateral sclerosis (ALS) patients from mainland China, as well as to characterize the relationship between OPTN mutation and clinical phenotypes. We examined the coding region of OPTN in 511 unrelated Chinese sporadic ALS (SALS) subjects and 204 healthy controls using a PCR direct sequencing strategy. Nine OPTN variants were identified, of which four were novel missense mutations: c.407C > T (p.A136V), c.1184A > G (p.K395R), c.1352T > C (p.I451T), and c.1546G > C (p.E516Q) (all heterozygous). The remaining five variants were already present in single nucleotide polymorphism databases. Patients with OPTN mutations were characterized by spinal onset, although they showed differences in disease progression. In conclusion, this study provides a genetic epidemiological characterization of OPTN mutations in Chinese patients, and our results are consistent with the proposition that such mutations are common in Asian populations.