# A 14‐Year Study of Serum Glial Fibrillary Acidic Protein and Total Tau in Premanifest Huntington's

## TL;DR

This 14-year study examines blood biomarkers in premanifest Huntington's disease and finds that glial fibrillary acidic protein and total tau are not useful for predicting disease onset.

## Contribution

First longitudinal and head-to-head study of serum glial fibrillary acidic protein and total tau in premanifest Huntington's disease.

## Key findings

- Serum glial fibrillary acidic protein and total tau do not show prognostic value in premanifest HD.
- Longitudinal analysis reveals no distinct dynamics for these biomarkers in premanifest/transitional HD.
- Contrasts with earlier findings on neurofilament light as a useful biomarker in HD.

## Abstract

There is a pressing need for blood biomarkers that can identify Huntington's disease (HD) gene carriers' proximity to manifest disease. We previously examined serial serum neurofilament light (NfL) concentrations in 21 premanifest HD gene carriers and 14 controls over 14 years, finding that NfL demonstrates high prognostic value and distinct longitudinal dynamics in premanifest/transitional HD. Here, we report the corresponding results for serum glial fibrillary acidic protein and total tau, providing the first longitudinal and head‐to‐head study of these biomarkers in HD. Our findings do not support the utility of these analytes as prognostic biomarkers in premanifest and transitional HD.