There are a number of unresolved research questions in spinal muscular atrophy, including whether we can correct SMN protein levels when symptoms are present, what is expected of biomarker measures, and the role of SMN on other organs and tissues.
Researchers have been studying SMA via mouse models for several years. The existing mouse models of SMA have been a tremendous asset for understanding what goes wrong in SMA and testing new drug candidates.
However, mice have some limitations when comparing them to human beings. Mice have a relatively permeable blood-brain barrier just after birth, and they also have other biological characteristics that aren’t typical of humans. A large animal model of SMA can help provide more of the information we need to assess if treatments might be safe and effective before they progress to human clinical trials.
Early results from the pig model show that high SMN levels are still needed in motor neurons even after birth, and that reducing SMN levels causes SMA symptoms. The results also show that biomarkers and tests like CMAP and MUNE, which are used to measure muscle function in individuals with SMA, show improvement with SMN restoration, even after the onset of symptoms.
Congratulations to Dr. Burghes and the rest of the authors on their accomplishment. Thank you for helping move SMA research forward!
(Pictured above: Dr. Burghes.)