It is becoming clear that a precise measure of MND disease progression is urgently required. Many research groups around the world have joined the search for the optimal biomarker. One of the simplest types of molecule to use as biomarkers are proteins. These can easily be measured in a patient's blood or spinal fluid. This has meant that many researchers are sampling MND patients' spinal fluid for proteins that change in concert with MND progression. An obvious place to start would be genes associated with familial MND. This is just what Professor Marklund in Sweden has done by examining the presence of mutant SOD1 in spinal fluid of familial MND patients. The researchers found that although they can detect SOD1 in spinal fluid it would not be a suitable biomarker. On the other hand, work coming out of Chiba in Japan showed that the product of the MND associated gene TDP-43 could be found increased in spinal cord fluid of MND patients. This was specific to MND and changed depending on the stage of the disease. These results mean that TDP - 43 shows promise as a biomarker.
Other protein biomarkers are also showing promise. Researchers at the University of Pittsburg, USA have shown that cystatin C has potential as an MND biomarker, while researchers in Sergpipe, Brazil have found that the presence of the neurofilament heavy chain in spinal fluid may also be a good predictor of MND. While protein levels in blood plasma and spinal fluid are easily detected and monitored, there may be less invasive ways to monitor MND progression. One such method has been published by Professor Matthew Keirnan's research group in Sydney. They have found that performing functional assessment and nerve conduction studies gives reliable information about MND progression. In addition, a group in the USA has shown that magnetic resonance spectroscopy may be useful as a biomarker. These studies may become very useful for the implementation of clinical trials.
Source: International MND research update - March 2011, Dr Justin Yerbury for MNDRIA