RAD21 and Cornelia de Lange syndrome: Seven genes associated with CDLS have been identified: nipped-B like protein (NIPBL), structural maintenance of chromosomes 1A (SMC1A) and 3 (SMC3), double-strand break repair protein rad21 homolog (RAD21), bromodomain-containing protein 4 (BRD4), histone deacetylase 8 (HDAC8), and ankyrin repeat domain-containing protein 11 (ANKRD11) [1,2,6,7,42,43,44,45].