A recurrent 15q13.3 microdeletion syndrome associated with mental retardation and seizures.

Academic Article


  • We report a recurrent microdeletion syndrome causing mental retardation, epilepsy and variable facial and digital dysmorphisms. We describe nine affected individuals, including six probands: two with de novo deletions, two who inherited the deletion from an affected parent and two with unknown inheritance. The proximal breakpoint of the largest deletion is contiguous with breakpoint 3 (BP3) of the Prader-Willi and Angelman syndrome region, extending 3.95 Mb distally to BP5. A smaller 1.5-Mb deletion has a proximal breakpoint within the larger deletion (BP4) and shares the same distal BP5. This recurrent 1.5-Mb deletion contains six genes, including a candidate gene for epilepsy (CHRNA7) that is probably responsible for the observed seizure phenotype. The BP4-BP5 region undergoes frequent inversion, suggesting a possible link between this inversion polymorphism and recurrent deletion. The frequency of these microdeletions in mental retardation cases is approximately 0.3% (6/2,082 tested), a prevalence comparable to that of Williams, Angelman and Prader-Willi syndromes.
  • Authors

    Published In

  • Nature Genetics  Journal
  • Keywords

  • Adolescent, Child, Child, Preschool, Chromosome Breakage, Chromosomes, Human, Pair 15, Female, Gene Deletion, Gene Frequency, Humans, Inheritance Patterns, Intellectual Disability, Male, Pedigree, Receptors, Nicotinic, Seizures, Syndrome, alpha7 Nicotinic Acetylcholine Receptor
  • Digital Object Identifier (doi)

    Author List

  • Sharp AJ; Mefford HC; Li K; Baker C; Skinner C; Stevenson RE; Schroer RJ; Novara F; De Gregori M; Ciccone R
  • Start Page

  • 322
  • End Page

  • 328
  • Volume

  • 40
  • Issue

  • 3