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Celia de Lange syndrome (CdLS;OMIM:122470)is characterized by distinctive facial features,growth retardation,hirsutism,and upper limb reduction defects.Craniofacial features manifest as synophrys,arched eyebrows,long thick eyelashes,a small upted nose,small widely-spaced teeth,and microcephaly.The intelligence quotient (IQ) is usually below the normal level.More phenotypes are frequently found,such as cardiac septal defects,gastrointestinal dysfunction,hearing loss,myopia,and cryptorchidism or hypoplastic genitalia.Some individuals suffering from milder forms of CdLS have less severe growth,cognitive,and limb involvement,but often have typical facial features.1 The prevalence of CdLS is estimated to be 1.6 to 2.2/100000 live births,without racial variation.2 Most cases are sporadic,and very few familial cases have been reported.Approximately 50%-60% of CdLS cases are caused by mutations in the Nipped-B-like (NIPBL) gene,which encode two isoform products termed delangin-A and delangin-B.