Notably, in our cohort we detected several Mendelian disorders of chromatin modification (chromatinopathies), including (with the associated gene in parentheses): CHARGE (CHD7), Kleefstra (EHMT1), Floating–Harbor syndrome (SRCAP), KAT6B-related disorders (KAT6B), and 2q37 deletion syndrome (caused by haploinsufficiency of the HDAC4 gene [30]). Here, HDAC4 is linked to Down syndrome.