Researchers used blood proteins from 53,014 UK Biobank participants to estimate aging in 16 organs and systems. They found 5,436 significant links to 1,059 diseases, including 655 that developed later and 404 already present; the findings do not prove causation.
Immune-system and liver aging showed particularly strong genetic connections with other body systems, and their aging patterns tended to correlate elsewhere. Repeated measurements from 1,006 people suggested changes involving the immune system, liver and stomach could sometimes precede aging changes in other systems; this does not show one organ causes another to age.
Researchers identified 261 genetic regions associated with the clocks and found relationships with 841 environmental and lifestyle factors. They also evaluated the clocks in 3,977 participants in the China Kadoorie Biobank, where the models continued to show useful aging patterns. The measures remain research tools, not routine medical tests, and the study did not show that changing an estimated organ age would lower disease risk.
