GRN and early-onset autosomal dominant Alzheimer disease: Remarkably, besides the recessive lysosomal storage disorder, neuronal ceroid lipofuscinosis, heterozygous loss-of-function variants in GRN also cause frontotemporal dementia, and common, noncoding variants that likely affect GRN gene expression appear to influence risk for PD, amyotrophic lateral sclerosis, and Alzheimer’s disease (97).