IDENTIFICATION OF STRUCTURAL CHROMOSOMAL REARRANGEMENTS IN CHILDREN WITH IDIOPATHIC MENTAL RETARDATION USING HIGH RESOLUTION CHROMOSOME ANALYSIS
Introduction. Diagnosis of genomic and chromosomal anomalies is based on the application of cytogenetic and molecular technologies.
The aim of the study. The objective of the work was the delivery and the use of the algorythm for diagnosis of structural genomic and chromosomal
anomalies based on high-resolution chromosome analysis and molecular cytogenetics methods in children with idiopathic mental retardation
Methods.High-resolution chromosome banding, molecular cytogenetic methods including fluorescence in situ hybridization (FISH) and molecular
karyotyping (array CGH) were used.
Results.Here we describe the results of cytogenetic and molecular cytogenetic studies of chromosomal/genomic microaberrations in 55 children with
idiopathic mental retardation, developmental delay and small dysmorphic features. In all of these cases classical cytogenetic studies did not reveal gross
microscopically detectable chromosomal aberrations. In order to detect or exclude unbalanced structural aberrations in these children we used a special
algorythm of chromosome analysis based on the combined application of high resolution G-banding, in situ hybridization (FISH-method) and DNA
microarrays (array CGH). Different types of chromosomal microaberrations in all of 55 children with mental retardation were identified.
Conclusion. Step by step application of high-resolution banding and modern molecular cytogenetic and genomic technologies allowed to reveal
microaberrations of genome (chromosome) and discover new etiological causes of idiopathic mental retardation and congenital malformation.
Keywords:
structural chromosomal anomalies, idiopathic mental retardation, fluorescent in situ hybridization (FISH), comparative genomic
hybridization on DNA chips (array CGH)