[JaCALS: a prospective multicenter ALS cohort study].

To investigate the longitudinal course of Japanese patients with Amyotrophic Lateral Sclerosis (ALS), we constructed a multicenter registration and follow-up system called Japanese Consortium for Amyotrophic Lateral Sclerosis research (JaCALS). Genomic DNA samples of ALS patients were stored and linked to the clinical information. We designed a telephone survey system using a clinical research coordinator (CRC) to check the score of the ALS Functional Rating Scale-R (ALSFRS-R) and the prognosis every 3 months. In January 2006, we began registering ALS patients, and, at present, 22 neurology facilities are participating in the JaCALS. Currently, 571 Japanese ALS patients are registered. From the longitudinal data of the 279 patients who were registered before September 2009, the older age at onset was a significant risk factor for not only earlier death or introduction of mechanical ventilation, but also earlier loss of speech, loss of swallowing function and loss of upper limb function. In collaboration with the RIKEN Center for Genomic Medicine, genome-wide association studies (GWAS) using 1,305 ALS samples from the JaCALS and BioBank Japan were conducted, which showed that ZNF512B gene was associated with susceptibility to ALS. The JaCALS has established an efficient registration and follow-up system with genomic DNA resources of ALS patients, and will contribute to identify ALS-associated genes and to promote clinical researches.