| Namespace | disease_ontology | Obsolete | false |
| description | A brain small vessel disease that is characterized by fragile small blood vessels in the brain, leukoencephalopathy, increased risk of stroke, seizure and migraine and in some cases Axenfeld-Riegar anomaly that has_material_basis_in autosomal dominant inheritance of heterozygous mutation in the collagen type IV alpha 1 chain gene (COL4A1) on chromosome 13q34. |