Neurodevelopmental disorders (NDDs) affect brain development and function, with varying symptoms and genetic causes. While some RAS superfamily proteins are known to contribute to NDDs, the role of SGSM (small G protein signaling modulator) remained unexplored. A recent study changed that, identifying an SGSM3 gene founder variant in 13 patients from 8 Ashkenazi Jewish families. This variant, shared by all affected members, likely impairs SGSM3 function, causing mild developmental delays, intellectual challenges, hypotonia, behavioral issues, and short stature. This discovery adds SGSM3 to the list of genes associated with NDDs, opening new avenues for research into its role in brain development and growth regulation. It is also expected to allow the diagnosis of dozens of undiagnosed Ashkenazi Jews individuals with NDD. (By Dr. Hagar Mor-Shaked, https://jmg.bmj.com/content/61/3/289 )