Hereditary Spastic Paraplegia (HSP) Support Group helps people diagnosed with HSP. They are a UK based charity, 

The group was started as a 'self-help' group in 1989 by Stephanie Wyatt to support her affected husband and son. Today they have nearly 400 members, but are always trying to reach more people affected by the condition. So, whether people have HSP, love someone with HSP or are searching for information about a diagnosis, this charity supports them so they don’t face it alone. Also money raised will provide research into HSP, including developing treatments and improving understanding.