Through collaborations facilitated by Genematcher36, Deciphering Developmental Disorders project37, and 100,000 Genomes Project38 we expanded our cohort to 19 individuals from 14 unrelated families, all sharing a clinical phenotype of neurodevelopmental delay and carrying distinct variants in EZH1 (Fig. 1, Supplementary Fig 1 and Supplementary Data 1), which supported the implication of EZH1 in the disease pathogenesis. Here, EZH1 is linked to Neurodevelopmental delay.