title: Cryptic chromosomal rearrangements in children with idiopathic mental retardation in the Czech population.
abstract: OBJECTIVE
  The aim of our study was to scan for cryptic rearrangements using the multiplex ligation probe amplification method in a cohort of 64 probands with mental retardation or developmental delays in combination with at least one of the following symptoms: hypotonia after birth, congenital anomalies, or face dysmorphisms; but without a positive cytogenetic finding. The study contributes to the knowledge of microdeletion syndromes and helps disclose their natural phenotypic variability.
  
  
  RESULTS
  In total, 10 positives (16%) were detected, particularly 3 duplications (Xpter-p22.32; 17p11.2; 22q11) and 6 different deletions (1p36; 7q11.23; 10p15; 15q11-q13; 17p11.2; 17p13.3), 1 of these in 2 probands. Besides the well-characterized syndromes, less-often described rearrangements with ambiguous phenotype associations were also detected.
  
  
  CONCLUSIONS
  Some rearrangements, particularly duplications, are associated with vague phenotypes; and their frequency could be underestimated.
authors.affiliation: Institute of Biology and Medical Genetics, 1st Faculty of Medicine and General Teaching Hospital, Charles University in Prague, Prague, Czech Republic. kzidk@lf1.cuni.cz
authors.forename: Katerina
authors.initials: K
authors.lastname: Hirschfeldova
authors.forename: Alice
authors.initials: A
authors.lastname: Baxova
authors.forename: Vera
authors.initials: V
authors.lastname: Kebrdlova
authors.forename: Roman
authors.initials: R
authors.lastname: Solc
authors.forename: Romana
authors.initials: R
authors.lastname: Mihalova
authors.forename: Petr
authors.initials: P
authors.lastname: Lnenicka
authors.forename: Kamila
authors.initials: K
authors.lastname: Vesela
authors.forename: Jitka
authors.initials: J
authors.lastname: Stekrova
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D002869:Chromosome Aberrations / Q000706:statistics & numerical data*; D002872:Chromosome Deletion; D025063:Chromosome Disorders / Q000453:epidemiology / Q000235:genetics; D002878:Chromosomes, Human, Pair 1 / Q000235:genetics; D002897:Chromosomes, Human, Pair 7; D015331:Cohort Studies; D018153:Czech Republic / Q000453:epidemiology; D005260:Female; D005828:Genetics, Population; D006801:Humans; D007223:Infant; D008607:Intellectual Disability / Q000453:epidemiology* / Q000235:genetics*; D008297:Male; D011218:Prader-Willi Syndrome / Q000453:epidemiology / Q000235:genetics; D018980:Williams Syndrome / Q000453:epidemiology / Q000235:genetics