In 2009, the OMIM database indicated the following loci for Seckel Syndrome: chromosomes 18p11-q11 (SCKL2, MIM:606744), 14q (SCKL3, MIM:608664) and 13q12 (SCKL4, MIM:613676), but causative mutations were only found in a single gene: ATR (ataxia-telangiectasia and RAD3-related protein, SCKL1) [25]. Here, ATR is linked to microcephalic primordial dwarfism.