GRN and Parkinson disease: Furthermore, GRN and/or TMEM106B polymorphisms are associated with FTLD caused by C9ORF72 mutations (van Blitterswijk et al, 2014; Deming & Cruchaga, 2014; Gallagher et al, 2014; Lattante et al, 2014), cognitive impairment in amyotrophic lateral sclerosis (ALS) (Vass et al, 2011) and Parkinson's disease (PD) (Baizabal‐Carvallo & Jankovic, 2016; Tropea et al, 2019), and pathological presentation of Alzheimer's disease (AD) (Lee et al, 2011; Rutherford et al, 2012; Kamalainen et al, 2013; Perry et al, 2013; Sheng et al, 2014; Xu et al, 2017).