Brain Small Vessel Disease 2, also known as porencephaly 2, is related to familial porencephaly and aortic valve prolapse, and has symptoms including hemiplegia, muscle spasticity and seizures. An important gene associated with Brain Small Vessel Disease 2 is COL4A2 (Collagen Type IV Alpha 2 Chain), and among its related pathways/superpathways are Cell adhesion_ECM remodeling and Platelet Aggregation Inhibitor Pathway, Pharmacodynamics. Affiliated tissues include brain, and related phenotypes are global developmental delay and spastic tetraplegia