This hypothesis is also supported by the finding that all three patients, affected by a novel severe malformation syndrome, carry FBRSL1 variants localizing to the N-terminal region of FBRSL1. Although these patients show overlapping features to patients with AUTS2 syndrome, which is caused by variants in the FBRSL1-paralog AUTS2, they have a higher rate and wider spectrum of congenital malformations. Here, FBRSL1 is linked to autism spectrum disorder due to AUTS2 deficiency.