SLIT2 and SATB2 associated disorder: Whilst further studies are required to show a causal relationship between loss of SLIT2 expression and the pathogenesis of SAs, in principle, the two hits we have found at SLIT2 – methylation and LOH – could promote tumorigenesis by a revised version of the Knudson two hit hypothesis [23], in which LOH renders an epimutation homozygous.