In the context of psychiatric disorders, IGF-2 peripheral levels have been previously studied in schizophrenia [29,30,31,32] and in neurodegenerative disorders that impair memory or cognitive status, such as Alzheimer’s disease [33,34,35], Huntington’s disease [36] and Parkinson’s disease [37]. This evidence concerns the gene IGF2 and early-onset autosomal dominant Alzheimer disease.