M Huntington's Disease Biomarkers Appear 24 Years Before Clinical Symptoms

Huntington's Disease Biomarkers Appear 24 Years Before Clinical Symptoms

Heidi Splete

 
•  
   
 
 

Early signs of neurodegeneration appeared in young adult carriers of the Huntington's disease gene mutation approximately 24 years before the clinical onset of symptoms, according to a study published in the June Lancet Neurology. The data come from the Huntington's disease Young Adult Study (HD-YAS) conducted in the United Kingdom.

The genetic cause of Huntington's disease provides a potential target for biomarker treatment, wrote joint first authors Rachael I. Scahill, PhD, and Paul Zeun, BMBS, of University College London and colleagues.

"A detailed characterization of the premanifest period in Huntington's disease is crucial for disease staging, informing the optimum time to initiate treatments, and identifying biomarkers for future trials in people with premanifest Huntington's disease (preHD)," they said.

Identifying Biomarkers of Pre-Huntington's Disease

For their study, the researchers recruited 64 young adults with presymptomatic Huntington's disease (preHD) and 67 controls, with an average age of 29 years. Brain imaging was conducted between Aug. 2, 2017, and April 25, 2019. Individuals with preexisting measurable cognitive and psychiatric disorders were excluded.

The researchers found no significant evidence of cognitive or psychiatric impairment in the preHD group at 23.6 years from the predicted onset of symptoms. The preHD group showed smaller putamen volumes, compared with controls, but this difference had no apparent relation to the timing of symptom onset, the researchers said.

Brain imaging revealed elevations in the CSF mutant huntingtin, neurofilament light protein (NfL), YKL-40, and plasma NfL among individuals with preHD, compared with controls. Of these, CSF NfL showed the highest effect size of measures in the study and showed a significant increasing association with estimated years to the onset of clinical symptoms of HD carriers. Overall, 53% of individuals with preHD had CSF NfL values in the normal range, and 47% had elevated values, compared with controls.

"NfL is therefore a potential candidate to provide a measure of disease progression in early preHD and might eventually be used as a marker of response to treatment in future preventive trials," the researchers said.