FBRSL1 (fibrosin like 1) is a paralog of the neurodevelopmental disorder gene AUTS2 that functions as an RNA-binding protein critical for embryonic development 1. The gene encodes multiple isoforms, with N-terminal short isoforms showing ubiquitous expression in fetal tissues and being essential for developmental processes 1. Mechanistically, FBRSL1 regulates chr12 remodeling by associating with transcription factor YY1 and controlling expression of epigenetic regulators BRPF1 and KAT6A 2. Additionally, FBRSL1 interacts with splicing factor SF3B1 and regulates alternative splicing of mdm2, a p53 negative regulator, thereby controlling p53-mediated apoptosis during neural crest differentiation 3. Heterozygous truncating de novo variants in FBRSL1 cause a recognizable neurodevelopmental syndrome characterized by microcephaly, global developmental delay, autism, craniofacial abnormalities, skeletal contractures, and congenital heart defects 14. The syndrome reflects disruption of N-terminal isoforms required for first heart field development, neural differentiation, and cranial neural crest formation 53. A common genetic variant (rs11610045) in FBRSL1 also shows association with Parkinson's disease risk in Chinese populations 6. This multifaceted role in transcriptional regulation and neural development positions FBRSL1 as an important developmental regulator whose dysfunction produces severe multisystem pathology.