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8p inverted duplication/deletion syndrome

Disease definition

A rare chromosomal anomaly clinically characterized by mild to severe intellectual disability, severe developmental delay (psychomotor and speech development), hypotonia with tendency to later develop progressive hypertonia, and characteristic facial features. The main congenital anomalies associated include central nervous system (CNS) malformations such as hypoplasia/agenesis of the corpus callosum (80%), skeletal abnormalities such as scoliosis/kyphosis or dislocated hips (60%), and congenital heart defects (25%).


Classification level: Disorder
  • Synonym(s):
    • Invdupdel(8p)
    • Inverted 8p duplication/deletion syndrome
  • Prevalence: <1 / 1 000 000
  • Inheritance: Not applicable or Unknown 
  • Age of onset: Infancy, Neonatal
  • ICD-10: Q99.8
  • ICD-11: LD41.P
  • OMIM: -
  • UMLS: C4273676
  • MeSH: -
  • GARD: -
  • MedDRA: -

Detailed information

General public


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