Diseases Studied
The Rare Diseases Clinical Research Network is an NIH-funded research network of 21 active consortia or research groups working to advance treatment for diseases that are rare. Use the search tools on this page to find the diseases we currently study. You can reach out to the indicated consortia or research groups for more information on those diseases and studies underway.
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All Diseases > Spastic paraplegia 4
Spastic paraplegia 4
Alternative Names: SPG4
Disease Category: Spastic Paraplegia
Hereditary spastic paraplegia type 4 (SPG4) is the most common form of hereditary spastic paraplegia, caused by pathogenic variants in the SPAST gene and accounting for approximately 40–50% of all HSP cases. SPG4 typically presents as a “pure” form of HSP, characterized by progressive lower-limb spasticity and weakness leading to a stiff, scissoring gait. Other common features include hyperreflexia, urinary urgency or bladder dysfunction, and mild loss of vibration sense in the feet. Symptom onset is highly variable, ranging from infancy to late adulthood, even within the same family. The SPAST gene encodes spastin, a protein crucial for microtubule severing and axonal transport; dysfunction results in degeneration of long corticospinal tract fibers. SPG4 is inherited in an autosomal dominant manner, with age-dependent and variable penetrance—some carriers may experience mild symptoms or remain asymptomatic.
Research groups studying this disease
Spastic Paraplegia
Spastic Paraplegia Centers of Excellence Research Network (SP-CERN)
CureSPG4 Foundation
Our mission is to increase awareness of SPG4 hereditary spastic paraplegia, provide a resource for patients and their families, and fund research to find a cure for SPG4 hereditary spastic paraplegia.
Lilly and Blair Foundation
What began as two families fighting for their daughters' futures has grown into a national movement — one that’s rewriting what’s possible for children with de novo SPG4.
In little more than two years, we’ve united families, scientists, and industry leaders. We’ve hosted three NIH and Boston Children’s Hospital-partnered scientific symposia, launched a global support network, and funded multiple research initiatives — including a gene therapy program now advancing toward clinical trials.
Our most recent fundraiser gathered 130 golfers, over 200 dinner guests, and raised more than $110,000 in a single night.
Today, The Lilly and Blair Foundation is a driving force in de novo SPG4 research, funding, and awareness.
The Maurya Koduri Foundation
Maurya Koduri Foundation was founded by Vamsi and Yashodha in 2023. Their 11 year old son, Maurya Koduri was diagnosed with de novo SPG4 hereditary spastic paraplegia. HSP has no cure. Since 2020, they have personally contributed and raised over $120,000 through various fundraisers and through this foundation. They have donated /granted over $55,000 grants to research to find a cure for hereditary spastic paraplegia. With HSP SPG4 being so rare, there is very little funding from the government. The costs for the research for human trials can be burgeoning and so they decided to establish a non profit organization to expand their horizons and reach out to a wider world. Maurya Koduri Foundation's mission is to increase awareness and fund research to find a cure for SPG4 hereditary spastic paraplegia.