INCL
Encyclopedia
INCL, also known as Infantile Neuronal Ceroid Lipofuscinoses or Santavuori 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 sufferers in total today – but relatively common in Finland
due to the local founder effect
.
. A variety of neurological symptoms, such as epilepsy
and myoclonic seizures, appear. The senses of hearing
and touch remain unaffected, and sufferers have been known to enjoy music
. The average lifespan of an INCL child is 9–11 years.
. Physiotherapy helps affected children retain the ability to remain upright for as long as possible, and prevents some of the pain.
Recent attempts to treat INCL with Cystagon have been unsuccessful.
Neuronal Ceroid Lipofuscinosis
Neuronal Ceroid Lipofuscinoses is the general name for a family of at least eight genetically separate neurodegenerative disorders that result from excessive accumulation of lipopigments in the body's tissues. These lipopigments are made up of fats and proteins...
and inherited as a recessive
Recessive
In genetics, the term "recessive gene" refers to an allele that causes a phenotype that is only seen in a homozygous genotype and never in a heterozygous genotype. Every person has two copies of every gene on autosomal chromosomes, one from mother and one from father...
autosomal
Autosome
An autosome is a chromosome that is not a sex chromosome, or allosome; that is to say, there is an equal number of copies of the chromosome in males and females. For example, in humans, there are 22 pairs of autosomes. In addition to autosomes, there are sex chromosomes, to be specific: X and Y...
genetic
Genetics
Genetics , a discipline of biology, is the science of genes, heredity, and variation in living organisms....
trait. The disorder is progressive, degenerative and fatal, extremely rare worldwide – with approximately 60 official cases reported by 1982, perhaps 100 sufferers in total today – but relatively common in Finland
Finland
Finland , officially the Republic of Finland, is a Nordic country situated in the Fennoscandian region of Northern Europe. It is bordered by Sweden in the west, Norway in the north and Russia in the east, while Estonia lies to its south across the Gulf of Finland.Around 5.4 million people reside...
due to the local founder effect
Founder effect
In population genetics, the founder effect is the loss of genetic variation that occurs when a new population is established by a very small number of individuals from a larger population. It was first fully outlined by Ernst Mayr in 1942, using existing theoretical work by those such as Sewall...
.
Presentation
The development of children born with INCL is normal for the first 8–18 months, but will then flounder and start to regress both physically and mentally. Motor skills and speech are lost, and optic athropy causes blindnessBlindness
Blindness is the condition of lacking visual perception due to physiological or neurological factors.Various scales have been developed to describe the extent of vision loss and define blindness...
. A variety of neurological symptoms, such as epilepsy
Epilepsy
Epilepsy is a common chronic neurological disorder characterized by seizures. These seizures are transient signs and/or symptoms of abnormal, excessive or hypersynchronous neuronal activity in the brain.About 50 million people worldwide have epilepsy, and nearly two out of every three new cases...
and myoclonic seizures, appear. The senses of hearing
Hearing (sense)
Hearing is the ability to perceive sound by detecting vibrations through an organ such as the ear. It is one of the traditional five senses...
and touch remain unaffected, and sufferers have been known to enjoy music
Music
Music is an art form whose medium is sound and silence. Its common elements are pitch , rhythm , dynamics, and the sonic qualities of timbre and texture...
. The average lifespan of an INCL child is 9–11 years.
Treatment
Treatment is limited. Drugs can alleviate the symptoms, such as sleep difficulties and epilepsyEpilepsy
Epilepsy is a common chronic neurological disorder characterized by seizures. These seizures are transient signs and/or symptoms of abnormal, excessive or hypersynchronous neuronal activity in the brain.About 50 million people worldwide have epilepsy, and nearly two out of every three new cases...
. Physiotherapy helps affected children retain the ability to remain upright for as long as possible, and prevents some of the pain.
Recent attempts to treat INCL with Cystagon have been unsuccessful.