NCL (NCL) is a group of hereditary progressive neurological lysosomal disorders, that cause an accumulation of autofluorescent lipopigments (ceroid lipofuscin) in the lysosomes of neurons and other cells.
NCL produce typically psychomotor impairment, loss of vision, ataxia, epileptic or seizure periods and premature death.
Mutations have been detected up to thirteen genes capable of producing NCL: ATP13A2, CLN3, CLN5, CLN6, CLN8, CTSD, CTSF, DNAJC5, GRN, KCTD7, MFSD8, PPT1 and TPP1. However, at the time of diagnosis have to take into account the great clinical and allelic heterogeneity that accompanies this disease.
The most common types of NCL are NCL2 (late infantile) and NCL3 (classic youth). And although in origin, NCLs were classified according to age of onset of symptoms (NCL1 or child, or late infantile NCL2, NCL3 or juvenile or adult NCL4), currently they are classified according to the gene affected.
NCLs have an autosomal recessive inheritance. In this case, parents of sick children have a normal and a mutant allele, and they would be asymptomatic. However, there is an exception in the case of NCL4 that can be inherited in an autosomal dominant or recessive.
NCLs are the most common progressive hereditary neuropathology in childhood, with a prevalence of approximately 1.5 -9 1,000,000,000 individuals. This number can vary between countries.
Bioarray has a NGS panel for sequencing of genes mainly involved in the development of NCL: CLN6; CLN8; TPP1, CLN3, PPT1; MFSD8; CLN5; CTSD.