Expanding the phenotype of <i>TARDBP</i> mutation in a Tunisian family with clinical phenotype heterogeneity.

We describe a Tunisian family carrier of the same rare mutation in <i>TARDBP</i> but developing different neurodegenerative disease with heterogenous features. We explored the possible genetic modifiers leading to the observed intrafamilial phenotypic variability. Genetic analysis identified <i>TARDBP</i> p.G294A mutation among4 members. Additionally, the ALS case was muted in <i>GBA</i>. While the three cases of AD were carriers of <i>PRKN</i> and <i>GBA</i> mutations. Finally, the FTD-parkinsonism patient was mutated for <i>LRRK2</i> p.G2019S that might increase his susceptibility to develop Parkinsonism spectrum. Genetic variants of <i>TARDBP</i> may influence the clinical manifestation in ALS case.