In collaboration with researchers from Germany, the USA, Tunisia and Iran we recently reported a new gene for hereditary spastic paraplegia (HSP).
The study, published in Nature Communications, also highlights a potential mechanism for the disease, which is already being targeted in drug trials for Alzheimer’s and Huntington’s diseases.
HSP is an inherited condition that causes stiffness and weakness in the leg muscles, often leading to patients becoming wheelchair-bound. Gradually getting worse over time, and with no treatments currently available, patients can only be offered muscle relaxants, which help the muscles to cope with the inability to move smoothly. Some patients with more complex forms of HSP can also have problems with their eyes, and intellectual impairment.
Several genes have already been linked with HSP, which causes degeneration of the nerves that lead down from the brain. But these genes only account for around two-thirds of patients with the condition. The new gene RNF170 identified gives doctors the opportunity to test for the disease in the other third of patients with no clear genetic diagnosis.
Our study also went on to try and understand the mechanism by which the gene mutations cause HSP using a zebrafish model and studies in cells. The results highlighted defects in the calcium signalling pathway essential for cell function. This pathway is already known to play a role in other diseases, such as Alzheimer’s and Huntington’s and so we hope that drugs being developed to tackle these diseases could also be used to improve treatments for HSP.