7q31.32 partial duplication: First report of a child with dysmorphism, autistic spectrum disorder, moderate intellectual disability and, epilepsy. Literature review

Abstract

IntroductionDuplication of long arm of chromosome 7(q) is uncommon. It may occur as “pure”, isolated anomaly or in association with other mutations involving the same or other chromosomes. “Pure” chromosome 7q duplication has recently been classified by segment involved: the interstitial, proximal, or distal segment of the arm. Attempts to correlate genotype with phenotype in each group has yielded questionable results even though intellective disability and minor dysmorphic features of variable types are typically seen. Material and MethodsIn a young boy showing minor facial dysmorphism, language delay, autistic spectrum disorder, epileptic seizures, behavioral disturbances and irritability an array-CGH analysis was carried out. ResultsArray-CGH analysis found in the proband a de novo variant of partial duplication of 7q31.32 (122.254.792–122.376.908). DiscussionA very few cases of partial 7q duplication have been reported thus far mainly presenting with clinical signs of dysmorphic features, large head, developmental delay, epileptic seizures and skeletal anomalies. To our knowledge, this is the first report of a case of a de novo variant of 7q31.32 duplication, showing dysmorphic anomalies and neurologic impairment including ASD and seizures. In the 7q31.32 region is located the gene CADPS2, which has been associated to autistic spectrum disorder and other neurologic disorders. In the child, a genotype-phenotype correlation may be hypothesized. Further similar reports may be useful to confirm this observation.