The Karolinska Institute in Sweden has established a consortium to develop molecular diagnostics for both Alzheimer's and Parkinson's disease. The new BIOMARKAPD program, launched in March, is part of the European Union's Joint Programme in Neurodegenerative Disease Research initiative.
In addition to refining data on known biomarkers typically found in cerebrospinal fluid from Alzheimer's or Parkinson's patients, BIOMARKAPD researchers are addressing some of the challenges associated with standardizing how biomarkers are measured and reported. As part of the program, McGill University's John Breitner is developing standardized ways to describe patient samples as a first step in bringing innovations to the clinic.
Genome Technology's Matthew Dublin recently spoke with Breitner about this work. What follows is an excerpt of their conversation, edited for space.
Genome Technology: How did BIOMARKAPD come together?
John Breitner: The EU's joint project in neurodegenerative diseases and a number of European governments primarily came together with the idea that it would be beneficial to sponsor an international collaborative effort. ... The [initial] call [for proposals] was for a consortium of labs in various participating countries that would undertake standardization of collection of biosamples for biomarkers in Alzheimer's disease research, processing, and analysis. So when bio labs say that an individual has a cerebrospinal fluid concentration of X for beta 42 and Y for Tau phosphory-lation, there's an international standard procedure which you would know if you run the same tests, you get the same results. There's been quite a lot of variation across laboratories ... which is obviously a major stumbling block to further advance molecular diagnostics for these diseases.
GT: How is the development of molecular diagnostics for neurodegenerative diseases progressing?
JB: What is now very well established is that these biomarkers can be useful to confirm or deny a presumptive diagnosis based on clinical testing or history. But what we don't have yet are standardized procedures for running these tests.
GT: What makes developing molecular diagnostics for Alzheimer's disease difficult?
JB: It's now clear that Alzheimer's disease has a very long phase where changes in the brain resulting from the disease processes have not yet reached the stage where they cause symptoms. ... It's very important to differentiate Alzheimer's disease from Alzheimer's dementia. There is now evidence that the disease is going on for decades before patients develop symptoms, and it's also clear that some of the biomarkers are abnormal in the presymptomatic phase, so there is a lot of interest there for early detection and prevention research.
GT: How close is the community to validating biomarkers for early detection?
JB: That is just now being seriously investigated. [As far as] the use of biomarkers for detection or measurement of the disease process in its presymptomatic stages, that is just beginning, and it's the major thrust of our research here. There is an enormous amount to learn about that — which biomarkers appear earlier, how reliable are they in predicting some changes, how rapidly they change over time, [and] is the disease process progressing — so that's a long way to clinical application, [but] it's an area of great interest.
GT: What has been the impact of next-generation sequencing on neurodegenerative disease research?
JB: It's very important to ... understand more about the fundamental causes or processes that lead to the characteristics of the disease. ... New genes that are being discovered are important, but they are relatively minor in terms of how much they contribute to a person's risk. The greater impact is what the genes tell us about the way the disease actually takes place.