Ribosomal Genes Activity in Aged Down Syndrome Subjects

Objective: We aimed to investigate whether rRNA 28S/18S levels decrease with aging in Down Syndrome (DS) individuals and whether these decreased levels are tissue-specific. Methods: We investigated mature rRNA 28S/18S levels by Northern Blotting in blood cells from 21 younger and 21 older DS individuals in comparison to 42 age-sex-matched controls. We also investigated these levels in oral mucosa and in blood cells from the same DS individuals. Results: All DS subjects showed no clinical signs of dementia at the time of the study. We did not detect differences in rRNA 28S/18S levels among DS and control groups concerning either aging process or cell types. Conclusions: Aging process in DS individuals was not characterized by reduced rDNA transcriptional activity and did not indicate a preclinical marker of AD in older DS subjects.