Huntington's Disease : Novel Blood Test Predicts Risk Of Onset And Progression

A simple blood test can now predict the risk of onset as well as rate of progression of Huntington’s disease in carriers as well as those affected by the disease, according to research led by scientists at UCL Huntington's Disease Centre, working with colleagues in Sweden, the USA, Canada, France and the Netherlands. "This is the first time a potential blood biomarker has been identified to track Huntington's disease so strongly," said the study's senior author, Dr Edward Wild, UCL Institute of Neurology.

The findings of their research have been published recently in Lancet Neurology.

Importance Of Blood Biomarker In Huntington’s Disease

A lot of research is going on worldwide in a bid to develop newer and better therapeutic options, or perhaps even find a cure for this debilitating neurodegenerative disease.

Currently, the best biomarkers to monitor disease progression include imaging and cerebrospinal fluid (CSF) analysis. Both these tests are more expensive and difficult for the patient compared to a blood test. Moreover, predicting onset and progression of this disease in asymptomatic individuals remains particularly challenging.

The blood test developed by the current research team tries to address these issues and could be a useful tool for Huntington’s disease research in the immediate future.

"We have been trying to identify blood biomarkers to help track the progression of HD for well over a decade, and this is the best candidate that we have seen so far," said Dr Wild, "Neurofilament has the potential to serve as a speedometer in Huntington's disease, since a single blood test reflects how quickly the brain is changing. That could be very helpful right now as we are testing a new generation of so-called 'gene silencing' drugs that we hope will put the brakes on the condition. Measuring neurofilament levels could help us figure out whether those brakes are working."

Measuring Neurofilament Levels In Blood – How The Study was Conducted

For their project, the research team estimated neurofilament levels from the blood samples of volunteers from the TRACK-HD study, an international project that followed 366 volunteers over a period of three years. The notable findings from their study included the following:

• Levels of neurofilament protein levels were elevated in all stages of the disease, even as early as the asymptomatic carrier stage in which persons were still a long way from developing visible clinical symptoms.
• The carriers showed neurofilament levels 2.6 times higher than in the controls.
• Levels of the protein kept increasing as the disease progressed from the asymptomatic stage to stage 2 of the disease.
• In the asymptomatic group, the baseline neurofilament levels at the start of the study predicted risk of onset i.e. subjects with high neurofilament levels were more likely to develop clinically overt disease in the next three years.
• After accounting for other factors known to predict the risk of onset and progression such as age and genetic markers, the blood levels of neurofilament marker still correctly predicted risk of onset, progression and brain atrophy as measured by MRI scanning.

Scope Of Measuring Blood Neurofilament Levels In The Future

• In the immediate future, the blood test might be a major tool to monitor disease progression in clinical trials to test out new drug options.

According to Dr Robert Pacifici, chief scientific officer of CHDI Foundation, a US non-profit Huntington's disease research foundation, "I can see neurofilament becoming a valuable tool to assess neuroprotection in clinical trials so that we can more quickly figure out whether new drugs are doing what we need them to. As a drug hunter, this is great news."

Advertisement

• In the distant future, should drugs to delay the progression of HD become available, the test could be used to guide treatment decisions.?

To conclude on a note of caution by the study’s lead author Lauren Byrne, "This is the first time neurofilament has been measured in blood, so much more work is needed to understand the potential and limitations of this test."

About Huntington’s Disease

Huntington’s disease or Huntington’s chorea is an inherited neurodegenerative condition typically starting around the 3rd or 4th decade. It progressively worsens and is characterized by abnormal involuntary writhing and dancing movements, cognitive dysfunction as well as psychiatric manifestations. Eventually the person becomes bed bound and dependent on others for daily living. Medications are available to control the symptoms but cannot halt the disease progression and death occurs in 10-30 years from onset.

References:

1. Blood test can predict onset and track progression of Huntington's disease - (https://www.eurekalert.org/pub_releases/2017-06/ucl-btc060617.php)

Source-Medindia