PARTIAL TRISOMY-3Q CAUSING MILD CORNELIA DE LANGE PHENOTYPE

A brother and sister are reported with developmental delay and facial features suggestive of the Cornelia de Lange syndrome. Cytogenetic ana lysis showed them to be trisomic for the region 3q25.1-26.2 because of the inheritance of an unbalanced interchromosomal insertion from thei r father, who was a balanced insertion carrier. The clinical phenotype and cytogenetic analysis (including chromosome painting studies) in r elation to the possible localisation of the Cornelia de Lange gene are discussed.