Furthermore, heterozygous loss-of-function variants of histone acetyltransferase KAT6B causes two different genetic disorders, Genitopatellar syndrome and SBBYSS syndrome (23), both of which are characterized by patellar hypoplasia, and a variety of growth phenotype that may include microcephaly and postnatal growth retardation, which has been proposed to be mediated by regulation of RUNX2 expression by KAT6B (24). This evidence concerns the gene KAT6B and blepharophimosis - intellectual disability syndrome, SBBYS type.