In humans, loss-of-function mutations in KMT2C have been associated to the appearance of ASD-like behaviors and Kleefstra syndrome 2 (Koemans et al., 2017; Satterstrom et al., 2020; Siano et al., 2022; Wu and Li, 2022), however limited information is available about the phenotype. This evidence concerns the gene KMT2C and Kleefstra syndrome 2.