Scientists from the University of Cologne have developed a method that allows determining the biological age of an organism with unprecedented accuracy - by transcriptome. The scientists called the new method BiT - binarized transcriptome aging clock. The results of the work are published in the journal Aging Cell.
All people age differently, and biological age can differ significantly from chronological age. Therefore, scientists are constantly looking for aging biomarkers that can be used to estimate the biological age of an organism. So far, methods of determining biological age have been based on the analysis of DNA, whose structure changes with age in the degree of methylation - the attachment of a methyl group to certain genes. Scientists track these epigenetic changes in the genome (epigenetic DNA tags) and use their set to estimate the body's aging level.
In the new work, specialists used a transcriptome, a set of genes that are read from DNA during the production of proteins, to estimate biological age. Previously it was not possible to develop an accurate aging clock based on gene activity because of the complexity of the method and the ambiguity of the results. The model organism for the experiment was the roundworm nematode Caenorhabditis elegans, whose lifespan is exactly known. By controlling external environmental factors, such as ultraviolet light or nutrition, scientists observed how the expression of about 1000 genes and the total lifespan of the organism changed.
The new aging clock allowed them to accurately predict the biological age of the worm, as well as the genes and environmental factors that accelerate and decelerate aging. They also found that immune response genes are important for the aging process, in addition to signal transduction in neurons. The researchers believe that the BiT method can be used to quickly and very accurately assess a person's biological age.