Notably, a meta-analysis of data from 796 AD patients discovered that those with late-onset AD (disease onset over 65 years of age) had a significantly higher CSF/serum albumin ratio than controls, and this ratio was also positively correlated with the concentration of both Aβ42 and neurofilament light chain (NFL) (a biomarker of neuronal damage) [77]. This evidence concerns the gene NEFL and Alzheimer disease.