Lysosomal storage diseases are a group of over 70 rare inherited metabolic disorders that result from defects in lysosomal function. Lysosomes are sacs of enzymes within cells that digest large molecules and pass the fragments on to other parts of the cell for recycling. This process requires several critical enzymes. If one of these enzymes is defective due to a mutation, the large molecules accumulate within the cell, eventually killing it.
Batten disease is a fatal disease of the nervous system that typically begins in childhood. Onset of symptoms is usually between 5 and 10 years of age. Often, it is autosomal recessive. It is the common name for a group of disorders called the neuronal ceroid lipofuscinoses (NCLs).
Neuronal ceroid lipofuscinosis is the general name for a family of at least eight genetically separate neurodegenerative lysosomal storage diseases that result from excessive accumulation of lipopigments (lipofuscin) in the body's tissues. These lipopigments are made up of fats and proteins. Their name comes from the word stem "lipo-", which is a variation on lipid, and from the term "pigment", used because the substances take on a greenish-yellow color when viewed under an ultraviolet light microscope. These lipofuscin materials build up in neuronal cells and many organs, including the liver, spleen, myocardium, and kidneys.
Infantile neuronal ceroid lipofuscinoses (INCL) or Santavuori disease or Hagberg-Santavuori disease or Santavuori-Haltia disease or Infantile Finnish type neuronal ceroid lipofuscinosis or Balkan disease is a form of NCL and inherited as a recessive autosomal genetic trait. The disorder is progressive, degenerative and fatal, extremely rare worldwide – with approximately 60 official cases reported by 1982, perhaps 100 with the condition in total today – but relatively common in Finland due to the local founder effect.
Battenin is a protein that in humans is encoded by the CLN3 gene located on chromosome 16. Battenin is not clustered into any Pfam clan, but it is included in the TCDB suggesting that it is a transporter. In humans, it belongs to the atypical SLCs due to its structural and phylogenetic similarity to other SLC transporters.
Palmitoyl protein hydrolase/thioesterases is an enzyme (EC 3.1.2.22) that removes thioester-linked fatty acyl groups such as palmitate from modified cysteine residues in proteins or peptides during lysosomal degradation. It catalyzes the reaction
Tripeptidyl-peptidase 1, also known as Lysosomal pepstatin-insensitive protease, is an enzyme that in humans is encoded by the TPP1 gene. TPP1 should not be confused with the TPP1 shelterin protein which protects telomeres and is encoded by the ACD gene. Mutations in the TPP1 gene leads to late infantile neuronal ceroid lipofuscinosis.
Sialin, also known as H(+)/nitrate cotransporter and H(+)/sialic acid cotransporter, is a protein which in humans is encoded by the SLC17A5 gene.
Ceroid-lipofuscinosis neuronal protein 6 is a protein that in humans is encoded by the CLN6 gene.
Protein CLN8 is a protein that in humans is encoded by the CLN8 gene.
Palmitoyl-protein thioesterase 1 (PPT-1), also known as palmitoyl-protein hydrolase 1, is an enzyme that in humans is encoded by the PPT1 gene.
Jansky–Bielschowsky disease is an extremely rare autosomal recessive genetic disorder that is part of the neuronal ceroid lipofuscinosis (NCL) family of neurodegenerative disorders. It is caused by the accumulation of lipopigments in the body due to a deficiency in tripeptidyl peptidase I as a result of a mutation in the TPP1 gene. Symptoms appear between ages 2 and 4 and consist of typical neurodegenerative complications: loss of muscle function (ataxia), drug resistant seizures (epilepsy), apraxia, development of muscle twitches (myoclonus), and vision impairment. This late-infantile form of the disease progresses rapidly once symptoms are onset and ends in death between age 8 and teens. The prevalence of Jansky–Bielschowsky disease is unknown; however, NCL collectively affects an estimated 1 in 100,000 individuals worldwide. Jansky–Bielschowsky disease is related to late-infantile Batten disease and LINCL, and is under the umbrella of neuronal ceroid lipofuscinosis.
A Finnish heritage disease is a genetic disease or disorder that is significantly more common in people whose ancestors were ethnic Finns, natives of Finland and Northern Sweden (Meänmaa) and Northwest Russia. There are 36 rare diseases regarded as Finnish heritage diseases. The diseases are not restricted to Finns; they are genetic diseases with far wider distribution in the world, but due to founder effects and genetic isolation they are more common in Finns.
Northern epilepsy syndrome (NE), or progressive epilepsy with mental retardation (EPMR), is a subtype of neuronal ceroid lipofuscinosis and a rare disease that is regarded as a Finnish heritage disease. Unlike most Finnish heritage diseases, this syndrome has been reported only in Finland. The disease is characterized by seizures in early childhood that progressively get worse until after puberty. Once the onset of seizures occurs, mental degradation is seen. This continues into adulthood, even after seizure frequency has decreased. The cause of the disease is a missense mutation on chromosome 8. The creation of a new protein occurs, and the lipid content of the brain is altered because of it. The ratio of the mutation carriers is 1:135. There is nothing that has been found to stop the progression of the disease, but symptomatic approaches, such as the use of benzodiazepines, have helped control seizures.
Major facilitator superfamily domain containing 8 also called MFSD8 is a protein that in humans is encoded by the MFSD8 gene. MFSD8 is an atypical SLC, thus a predicted SLC transporter. It clusters phylogenetically to the Atypical MFS Transporter family 2 (AMTF2).
Potassium channel tetramerisation domain containing 7 is a protein in humans that is encoded by the KCTD7 gene. Alternative splicing results in multiple transcript variants.
Kufs disease is one of many diseases categorized under a disorder known as neuronal ceroid lipofuscinosis (NCLs) or Batten disease. NCLs are broadly described to create problems with vision, movement and cognitive function. Among all NCLs diseases, Kufs is the only one that does not affect vision, and although this is a distinguishing factor of Kufs, NCLs are typically differentiated by the age at which they appear in a patient
Cerliponase alfa, marketed as Brineura, is an enzyme replacement treatment for Batten disease, a neurodegenerative lysosomal storage disease. Specifically, Cerliponase alfa is meant to slow loss of motor function in symptomatic children over three years old with late infantile neuronal ceroid lipofuscinosis type 2 (CLN2). The disease is also known as tripeptidyl peptidase-1 (TPP1) deficiency, a soluble lysosomal enzyme deficiency. Approved by the United States Food and Drug Administration (FDA) on 27 April 2017, this is the first treatment for a neuronal ceroid lipofuscinosis of its kind, acting to slow disease progression rather than palliatively treat symptoms by giving patients the TPP1 enzyme they are lacking.
Erika F. Augustine is an Associate Chief Science Officer and Director of the Clinical Trials Unit at Kennedy Krieger Institute. She was previously an Associate Professor of Neurology and Pediatrics at the University of Rochester Medical Center in Rochester, New York. Augustine co-directed the University of Rochester Batten Center, and was the associate director of both the Center for Health and Technology and the Udall Center of Excellence in Parkinson's Disease Research. Augustine's clinical research and medical practice specialize in pediatric movement disorders. She leads clinical trials for Batten diseases, a group of rare pediatric neurodegenerative disorders, and she has developed a novel telemedicine model to increase the efficacy of remote care for patients with rare diseases.
