Developmental delay is often a predictor of mental retardation (MR) or autism, two relatively frequent developmental disorders severely affecting intellectual and social functioning. The causes of these conditions remain unknown in most patients. They have a strong genetic component, but the specific genetic defects can only be identified in a fraction of patients. Recent developments in genomics supported the establishment of the causal link between copy number variants in the genomes of some patients and their affection. One of the techniques suitable for this analysis is array comparative genome hybridization, which can be used both for detailed mapping of chromosome rearrangements identified by classical cytogenetics and for the identification of novel submicroscopic gains or losses of genetic material. We illustrate the power of this approach in two patients. Patient 1 had a cytogenetically visible deletion of chromosome X and the molecular analysis was used to specify the gene content of the deletion and the prognosis of the child. Patient 2 had a seemingly normal karyotype and the analysis revealed a small recurrent deletion of chromosome 1 likely to be responsible for his phenotype. However, the genetic dissection of MR and autism is complicated by high heterogeneity of the genetic aberrations among patients and by broad variability of phenotypic effects of individual genetic defects.

• MeSH
• chromozomální delece MeSH
• dítě MeSH
• genetické nemoci vázané na chromozom X genetika   MeSH
• genom lidský MeSH
• lidé MeSH
• lidské chromozomy X genetika   MeSH
• lidské chromozomy, pár 1 genetika   MeSH
• novorozenec MeSH
• předškolní dítě MeSH
• srovnávací genomová hybridizace MeSH
• vývojové poruchy u dětí genetika   MeSH
• Check Tag
• dítě MeSH
• lidé MeSH
• mužské pohlaví MeSH
• novorozenec MeSH
• předškolní dítě MeSH
• Publikační typ
• časopisecké články MeSH
• kazuistiky MeSH
• práce podpořená grantem MeSH