IGF1R and major depressive disorder: However, genetic association analysis of polymorphisms in 10 genes belonging to the IGF-I system (IGF1, IGF1R, IGFBP1 to IGFBP7, and IGFBPL1) in the largest genetic databases for major depression (Psychiatric Genomics Consortium) revealed nominal associations with susceptibility to depression and treatment response, although results were not remain significant after multiple testing correction [27].