RESUMO
BACKGROUND: The nucleolar organizer regions (NORs) are localized at the secondary constriction of the five pairs of acrocentric chromosomes (13, 14, 15, 21 and 22) in human. MATERIALS AND METHODS: To evaluate whether increasing AgNOR protein synthesis effects or not the development of babies/children, 25 Down syndrome patients were included in this study. Firstly, the Ankara Development Screening Inventory (AGTE) test was performed. Then the buccal epithelial cells of patients were taken via a sterile toothpick on clean glass slides and spreaded and AgNOR staining technique was applied to the slides of each individual. Mean NOR area/Total nucleus area (NORa/TNa) were evaluated for each nucleus using a special computer program. RESULTS: The mean NORa/TNa was found to be 3.8+/-1.16. According to these data, a significant correlation was not evident between the NORa/TNa and developmental stages (p>0.05). CONCLUSIONS: There is no correlation between extra energy spending for NOR protein synthesis and developmental deficiency.