Pediatr. praxi. 2011;12(6):380-384
Mental retardation in children and adults is a serious medical and social problem. There are many causes of mental retardation, but
specific reason is found in only 25 % of cases. Recent progress in cytogenetic methods explained etiology of 10 % before unexplained
mental retardation due to detection of subtelomeric rearrangements, not visible by conventional cytogenetic analysis. The authors
refer about this modern diagnostic tools and present a case report of 4-years-old boy, who was investigated since infancy because of
clinical symptoms of severe mental retardation. Only at the age of 4 years, when multiprobe FISH method was introduced to specify
genetic diagnostic the authors were able to identify the subtelomeric deletion of chromozome 8 and telomeric trisomy of chromozome
12 – deletion in subtelomeric area 8p and trisomy in telomeric area 12p, which the child inherited from his healthy mother. Cytogenetic
examination of subtelomeric rearrangement of chromozomes provide only two hospitals in Czech Republic – our department in Ostrava
and Department of Biology and Medical Genetics University hospital Motol and 2nd Faculty of Medicine, Charles University Prague.
Published: December 10, 2011 Show citation