However, despite the increased levels of total tau and phosphorylated tau and the decreased levels of Aβ1-42 in the CSF derived from AD patients compared with the control group, total tau, phosphorylated tau, and Aβ1-42 levels in the CSF were not influenced by this rs2069456 SNP in the CDK5 gene [61]. Here, CDK5 is linked to Alzheimer disease.