Porencephaly is defined as a cavity in the cerebral parenchyma that results in hemiplegia, hydrocephalus, epilepsy, mental retardation with poor/absent speech, dystonia and optic and pituitary defects. Cerebral haemorrhage/stroke in affected individuals can happen in the fetal period, in childhood or in adulthood.  COL4A1 and COL4A2 disease-causing variants have been reported in families with autosomal dominant porencephaly (Gould et al 2005 Science 308(5725), 1167-1171van der Knaap et al 2006 Ann Neurol 59(3), 504-511Breedveld et al 2006 J Med Genet 43(6), 490-495Yoneda et al 2012 Am J Hum Genet 90, 86-90).

A much wider phenotype HANAC (Hereditary Angiopathy, Nephropathy, Aneurysms, and muscle Cramps) syndrome has also been described (Plaisier et al 2007 N Engl J Med 357(26), 2687-2695) and Brain Small-vessel Disease with Hemorrhage, as well as a muscle-eye-brain disease phenotype (Labelle-Dumais et al 2011 PLoS Genet 7(5), e1002062)

The laboratory participates in the European Molecular Genetics Quality Network (EMQN) sequencing scheme.