GRN and amyotrophic lateral sclerosis: A recent meta-analysis studied the association between the GRN polymorphism rs5848 and risk of neurodegenerative diseases, including FTLD, AD, Parkinson’s disease (PD), and ALS, concluding that rs5848 was associated with an increased risk of AD and PD in the homozygous and recessive models but not with FTLD (Chen et al., 2015).