- Edwards syndrome [DOID:1085]
A chromosomal duplciation syndrome that is characterized by slow growth before birth and a low birth weight and that has_material_basis_in three copies of chromosome 18.
- juvenile spinal muscular atrophy [DOID:12376]
A childhood spinal muscular atrophy that has age of onset after 18 months and is characterized by muscle weakness after early childhood and the ability to stand and walk.
- juvenile myoclonic epilepsy [DOID:4890]
A adolescence-adult electroclinical syndrome that is characterized by brief, involuntary twitching of a muscle or a group of muscles (myoclonus) early in the morning with onset between 12 and 18 years.
- hereditary spastic paraplegia 7 [DOID:0110816]
A hereditary spastic paraplegia that is characterized by slowly progressive onset, usually between 18-60 years of age, and generally more severe spasticity and has_material_basis_in mutation in the SPG7 gene on chromosome 16q24.
- Lafora disease [DOID:3534]
A progressive myoclonus epilepsy characterized by myoclonus and/or generalized seizures, visual hallucinations, and progressive neurological decline with onset between 8 and 18 years of age that has_material_basis_in homozygous or compound heterozygous mutation in either NHLRC1 on chromosome 6p22.3 or EPM2A on chromosome 6q24.3.
- nonspecific interstitial pneumonia [DOID:2801]
An idiopathic interstitial pneumonia that occurs mainly in women, people who do not smoke, and people younger than 50 years with no known cause or risk factors. Lung biopsies may show predominantly interstitial inflammation or fibrosis or a combination of inflammation and fibrosis. A dry cough and shortness of breath develop over 6 to 18 months. Low-grade fever and a feeling of illness (malaise) may occur.