As the euchromatic histone methyltransferase-1 gene (EHMT1, GLP, or KMT1D) within the 9q34 region is deleted or mutated in most of the individuals with KS, its absence or defect in one allele is speculated to cause the major symptoms of the syndrome.
Kleefstra Syndrome (KS) (MIM# 610253) is an autosomal dominant disorder caused by haploinsufficiency of euchromatic histone methyltransferase-1 (<i>EHMT1,</i> GLP).