NLGN4X and autism: Non-syndromic autism accounts for autism cases that are not linked to any neurological disorders.2Neuroligin is trans-synaptic cell adhesion molecule present post-synaptically and plays a very important role in synaptogenesis with presynaptic neurexin.3Humans have neuroligin 4X [NLGN4X] on the X chromosome and neuroligin 4Y [NLGN4Y] on the Y chromosome.NLGN4XandNLGN4Ygenes share 97% sequence identify.4The male bias seen fromNLGN4Xmutations is unclear sinceNLGN4Yplays a function similar toNLGN4Xand should be sufficient to reimburse forNLGN4XASD-related mutations.