Compared to the GWAS using global gray matter volume as the phenotype, our GWAS revealed additional signal in chromosome 7 (rs7776725), which was mapped to the intron of FAM3C and encodes a secreted protein involved in pancreatic cancer (Grønborg et al., 2006) and Alzheimer’s disease (Liu et al., 2016). This evidence concerns the gene FAM3C and early-onset autosomal dominant Alzheimer disease.