Furthermore, homozygous mutations in ESCO2, which encodes a cohesion acetyltransferase (CoAT; Nasmyth, 2011; Higashi et al., 2012), were found to underlie a second human disorder, Robert’s Syndrome (RBS; OMIM 268300; Vega et al., 2005). The gene discussed is ESCO2; the disease is Roberts-SC phocomelia syndrome.