Two Rare Variants of the ANXA11 Gene Identified in Chinese Patients with Amyotrophic Lateral Sclerosis

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disorder. A recent study has identified mutations in the ANXA11 gene (encoding the calcium-binding protein annexin A11) associated with ALS. Mutation screening of ANXA11 protein-coding exons was performed in a Chinese cohort of 434 patients with sporadic ALS and 50 index patients with familial ALS. Polymerase chain reaction and Sanger sequencing were used for mutation detection. We failed to discover an N-terminal mutation, which was common in the Caucasian cohort. We revealed two rare heterozygous missense variants, c.878C>T (p.A293V) and c.921C>G (p.I307M), which are absent from the population databases and non-neurological controls. They are both located in the conserved annexin domain. The carriers of the mutation exhibited the classical ALS phenotype without cognitive impairment. Our results suggested that further functional studies for these variants are required to support the pathogenicity.