What role does VDR play in Langlebigkeit?

The provided context documents contain no specific information on the role of the vitamin D receptor (VDR) in longevity. In general, VDR is a nuclear receptor activated by vitamin D, regulating genes involved in calcium metabolism, immune function, and cell proliferation. Epidemiological studies suggest associations between low vitamin D levels and increased mortality, but evidence for a direct causal role of VDR variants in human longevity is limited and often confounded. Without concrete data from the given material, a well-founded statement is not possible. The evidence rating is therefore unclear.