Neuronal Ceroid-Lipofuscinosis (PPT1-Related) (PPT1)
Neuronal ceroid-lipofuscinosis (PPT1-related) is an autosomal recessive neurodegenerative disorder that is caused by pathogenic variants in the gene PPT1. While it is found in different ethnicities around the world, it is more prevalent in individuals of Finnish descent due to the presence of a founder mutation. Most PPT1-caused neuronal ceroid-lipofuscinosis results in the infantile form, in which symptoms begin in infancy. Clinical features include progressive visual loss with blindness by the age of 2 years and neurologic symptoms, including seizures, ataxia, progressive cerebral atrophy, and intellectual disability. Affected children do not survive beyond childhood. Rarely, patients may be diagnosed with a later-onset form. It is not currently possible to predict the age of disease onset based on the patients genotype.
For information about carrier frequency and residual risk, please see the residual risk table.