Arginine codon 439 (CGC) wast targeted for change to a histidine codon (CAC)(c.1316G>A, p.R439H) with an sgRNA and an ssODN template (ACCAGAGAGCTTGCCTGCCGTCCGGGACTTTTCTGACTTGTTCCTCAGACAATACCATCCACTTCTGGAATTTGGATAGCGCCTCTGACACTCGATGGCAAAAGAACATCTTCAGCGATGT ) using CRISPR/Cas9 technology. The mutation mimics the p.R438H mutation found in some patients presenting with microcephaly or cortical malformations. (J:285212)