Lack of relationship between the P413L chromogranin B variant and a SALS Italian cohort

Chromogranins were reported to interact specifically with mutant forms of superoxide dismutase that are linked to amyotrophic lateral sclerosis (ALS). Particularly, a variation c.1238C>T (p.Pro413Leu) in the chromogranin B gene, CHGB, has been associated with an earlier age at onset in both familial and sporadic ALS in French/French-Canadian populations studied. The aim of our study was to evaluate the P413L chromogranin variation in Italian patients with sporadic ALS. The study included 366 Italian patients with sporadic ALS and 382 control subjects. Genotyping of the polymorphism P413L in the CHGB gene was performed and the clinical characteristics of patients were analyzed in relation to their genotype. Our study on a cohort of Italian patients with SALS and controls failed to confirm an increased frequency of the 413L variant in SALS patients. Furthermore, we did not confirm the previous observation of a difference of age at onset between T-allele carriers and non-carriers (median age of onset 58.5 vs. 60.2years of age, respectively). Our findings do not support the 413L variant as a risk factor for sporadic ALS in the Italian population.