PROGRANULIN

Progranulin is a biomarker that is particularly useful in the evaluation of neurodegenerative diseases (Alzheimer's and Frontotemporal Dementia); its assay is performed as an aid to related diagnosis.

Progranulin is a highly conserved secretion protein of 593 aa encoded by the GRN gene on human chromosome 17q21.

This protein has several functions including promoting the survival and growth of neocortical, hippocampal and motor neurons. It also has a neuroprotective effect by promoting β-amyloid cleareance and preventing hyperphosphorylation of the Tau protein.

Progranulin is secreted into biological fluids and can be measured in the patient's plasma and cerebrospinal fluid. More than 100 deleterious GRN mutations have been identified that can cause a loss of about 50 per cent of functional progranulin. This decrease in circulating progranulin levels may favour the onset of neurodegenerative diseases such as Alzheimer's disease (AD) and frontotemporal dementia (FTD). The plasma level of progranulin has been identified as an efficient marker to predict mutations in the GRN gene when decreased or undetectable; therefore, it can be used as an aid in the diagnosis of neurodegenerative diseases.