PCDH15 and Behcet disease: Having defined the phenotype of iPSC-derived neurons from patients with BD/SCZ carrying heterozygous PCDH15/RELN deletions, Ishii et al. [33] applied targeted genome editing (CRISPR/CAS9) (clustered regulatory interspaced short palindromic repeats/CRISPR-associated protein 9) to introduce patient-like mutations in two healthy control iPSCs.