NLGN1 and schizophrenia: However, our GWAS analysis appears to confirm several genes identified by our unsupervised analysis as shared risk variants in diabetes and schizophrenia, such as ERBB4 and NLGN1. NLGN1 is an interesting hit, for its role in the interaction of endothelial cells with extracellular matrix during angiogenesis and its downregulation in diabetic patients [55].