Objective: Piwi-interacting RNAs (piRNAs) represent a molecular feature shared by all nonaging biological systems, including the germline and somatic cancer stem cells, which display an indefinite renewal capacity and lifespan-stable genomic integrity and are potentially immortal. Here, we tested the hypothesis that piRNA is a critical genetic determinant of aging in humans.
Methods: Expression of transcriptome-wide piRNAs (n=24k) was profiled in the human prefrontal cortex of 12 subjects (84.9±9.5, range 68-100, years of age) using microarray technology. We examined the correlation between these piRNAs' expression levels and age, adjusting for covariates including disease status.
Results: A total of 9,453 piRNAs were detected in brain. Including seven intergenic and three intronic piRNAs, ten piRNAs were significantly associated with age after correction for multiple testing (|r|=0.9; 1.9×10-5≤p≤9.9×10-5).
Conclusion: We conclude that piRNAs might play a potential role in determining the years of survival of humans. The underlying mechanisms might involve the suppression of transposable elements (TEs) and expression regulation of aging-associated genes.
Keywords: Alzheimer’s disease; aging; brain; gene expression; piRNA; transposable elements (TEs); years of survival.