NRXN1 and autism: Of note, in this context, is that L1 interacts with the methyl CpG binding protein 2 [33,73] and topoisomerase 1 [27], and that disruption of the L1-70 interaction with topoisomerase 1 leads to changes in the expression of the long autism genes neurexin 1 and neuroligin 1 [27].