Myoclonus dystonia plus syndrome due to a novel 7q21 microdeletion

• Published in: American journal of medical genetics. Part A Vol. 152A; no. 5; pp. 1244 - 1249
• Main Authors: Saugier-Veber, Pascale, Doummar, Diane, Barthez, Marie-Anne, Czernecki, Virginie, Drouot, Nathalie, Apartis, Emmanuelle, Bürglen, Lydie, Frebourg, Thierry, Roze, Emmanuel
• Format: Journal Article
• Language: English
• Published: Hoboken Wiley Subscription Services, Inc., A Wiley Company 01-05-2010; Wiley-Liss
• Subjects: 7q21 microdeletion; Adolescent; Adult and adolescent clinical studies; Biological and medical sciences; Child; Chromosome Deletion; Chromosomes, Human, Pair 7 - genetics; Classical genetics, quantitative genetics, hybrids; Dystonia - complications; Dystonia - genetics; epsilon-sarcoglycan; Female; Fundamental and applied biological sciences. Psychology; Genetics of eukaryotes. Biological and molecular evolution; growth retardation; Human; Humans; Infant, Newborn; Intellectual deficiency; Male; Medical genetics; Medical sciences; mental retardation; Myoclonus - complications; Myoclonus - genetics; myoclonus dystonia; Nervous system (semeiology, syndromes); Nervous system as a whole; Neurology; Polymerase Chain Reaction; Pregnancy; Psychology. Psychoanalysis. Psychiatry; Psychopathology. Psychiatry; SGCE gene; Syndrome; Genetic mapping; Microdeletion; Nervous system diseases; Drug combination; Myoclonus; epsilon-sarcoglycan; myoclonus dystonia; SGCE gene; Developmental disorder; Mental retardation; Growth retardation; Involuntary movement; Cerebral disorder; Striated muscle disease; Gene; Central nervous system disease; 7q21 microdeletion; Intellectual deficiency; Genetics; Dystonia; Neurological disorder; Extrapyramidal syndrome
• ISSN: 1552-4825; 1552-4833
• DOI: 10.1002/ajmg.a.33369

Myoclonus dystonia (M‐D) is a rare genetic movement disorder characterized by a combination of myoclonic jerks and dystonia. It is usually due to mutations in the SGCE gene. We report on a patient with a typical M‐D syndrome, but also short stature, microcephaly, and mental retardation. Molecular analysis showed no mutations within the SGCE gene but a microdeletion encompassing the SGCE gene in chromosome region 7q21. Array‐CGH analysis showed that the deletion spanned approximately 1.88 Mb. We suggest that M‐D plus patients with mental retardation, microcephaly, dysmorphism, or short stature, all frequently associated disorders, should be screened for 7q21 microdeletion. By examining previously published cases of mental retardation associated with pure 7q21 deletions, we identified two distinct regions of respectively 455 and 496 kb that are critical for mental retardation and growth retardation. Among the genes located within these regions, LOC253012, also known as HEPACAM2, is a good candidate for both mental retardation and microcephaly. © 2010 Wiley‐Liss, Inc.