A drop of blood holds not only cells but also marks on DNA that shift with disease and lifestyle. These marks can be read like the tape of an old chart recorder, revealing what has been happening inside the body. Scientists created 1694 models that use such marks to predict what ordinary blood tests would show: levels of sugar, cholesterol, and proteins.
The models were trained on data from 4418 people who had both marks and test results. They were then tested on 57,454 people from different groups. It turned out that the predictions are often more strongly linked to disease than the tests themselves, because the marks accumulate information over months rather than a single day. This makes it possible to assess the risk of diabetes, heart disease, and other conditions from one blood sample.
The proxy for urate accurately predicted sex: men have higher urate levels, which matches the known sexual dimorphism.
In the series Altered Carbon, consciousness is transferred between bodies, and here DNA methylation acts as a "backup copy" of biological state, making it possible to reconstruct a picture of health from a single sample.
Not published on arXiv. Here are its page, the PDF and the formalization: you can check it yourself, not only read our account.